NQE Qualifying Exam Problem Bank 200

Categories			Problems	Rate
Major	Introduction to Nuclear Engineering(1)	100Problems	140 Problems	70%
	Radiation Detection(2)	10Problems
	Materials(3)	10Problems
	Fuel Cycles(4)	20Problems
Mathematics	Advanced Engineering Mathematics(5)		60 Problems	30%
Total	2 Subjects (Major + Mathematics)		200 Problems	100%

→ References : (1) J. R. Lamarsh and A. J. Baratta의 Introduction to Nuclear Engineering

3rd edition의 Chapter 2, 3, 5, 6, 8 & 9.

(2) G. F. Knoll의 Radiation Detection and Measurment, 3rd edition의

Chapter 3-IV, 4-IV, VI & VII, 6-I, 7-IV, 14-II, 10-II & III, 17-VI.

(3) Donald R. Askeland, Pradeep P. Phule, The Science and Engineering of

Materials, 5th edition, 2006. Chapter 6,7,8,11,12.

William F. Smith, Foundations of Materials Science and Engineering,

3rd edition, 2004. Chapter 12.

B. M. Ma, Nuclear Reactor Materials and Applications, 1983, Chapter 4,5

(4) W. Loveland, D. J. Morrissey, and G. T. Seaborg의 Modern Nuclear

Chemistry, Wiley Interscience, Chapter 15 & 16.

G. R. Choppin, J. O. Liljenzin, and J. Rydberg의 Radiochemistry and

Nuclear Chemistry, Butterworth-Heinemann, 3rd edition의 Chapter 15 & 21.

(5) D. G. Zill and M. R. Cullen 의 Advanced Engineering Mathematics

3rd edition의 Chapter 2, 3, 8, 12, 13 & 15.

I. Introduction to Nuclear Engineering

1. Chapter 2

1. Problem 6  p.46

2. Problem 7  p.46

3. Problem 13  p.46

4. Problem 14  p.46

5. Problem 15  p.46

6. Problem 16  p.47

7. Problem 25  p.47

8. Problem 28  p.47

9. Problem 29  p.48

10. Problem 33  p.48

12. Problem 37  p.48

12. Problem 39  p.49

13. Problem 40  p.49

14. Problem 43  p.49

15. Problem 45  p.49

16. Problem 50  p.50

17. Problem 52  p.50

18. Problem 57  p.51

19. Problem 60  p.51

20. Problem 62  p.51

2. Chapter 3

21. Example 1  p.55

22. Example 7  p.61

23. Example 9  p.67

24. Example 15. Here, m/r = 0.0757 cm2/gforuraniumand0.0636cm2/gforoxygen.  p.99

25. Example 16. Here, ma/r = 0.0274 cm2/g.  p.100

26. Problem 3  p.110

27. Problem 9  p.111

28. Problem 26  p.112

29. Problem 39  p.113

30. Problem 52  p.115

31. Problem 54  p.115

32. Problem 61  p.115

33. What is “ionizing radiation”?

34. What are the three main energy loss mechanisms of g -ray when it enters a material ?

35. Explain Bragg peak.

36. What is the difference between LET and stopping power ?

37. If the energies of two particles, an electron and a heavy charged particle, are the              same, which of the two has a higher range ? What is the reason ?

38. Make a plot of cross section versus energy of g-ray for photoelectric effect, Compton          scattering, and pair production.

39. Give an example of charged-particle reactions induced by a neutron.

40. Derive the collisional parameter in elastic scattering collision.

3. Chapter 5-6

(Chapter 5)

41. Problem 1  p.260

42. Problem 2  p.260

43. Problem 4  p.260

44. Problem 5  p.261

45. Problem 7  p.261

46. Problem 8  p.261

47. Problem 9  p.261

48. Problem 10  p.261

49. Problem 11  p.261

50. Problem 12  p.261

51. Problem 13  p.261

52. Problem 14  p.262

53. Problem 15  p.263

54. Problem 18  p.263

55. Problem 34  p.265

(Chapter 6)

56. Problem 3  p.322

57. Problem 4  p.322

58. Problem 6  p.322

59. Problem 10  p.322

60. Problem 21  p.324

61. Problem 23  p.324

62. Problem 24  p.324

63. Problem 30  p.325

64. Problem 31  p.325

65. Problem 34  p.325

66. Problem 39  p.326

67. Problem 40  p.326

68. Example 2  p.282

69. Example 3  p.283

70. Example 4  p.285

4. Chapter 8

71. Example 3  p.413

72. Example 4  p.416

73. Example 5  p.426

74. Example 7  p.435

75. Example 10  p.448

76. Example 12  p.457

77. Problem 2  p.459

78. Problem 3&4  p.459

79. Problem 6  p.459

80. Problem 7  p.459

81. Problem 8  p.459

82. Problem 13  p.460

83. Problem 24  p.462

84. Problem 29  p.462

85. Problem 31  p.463

86. Problem 33  p.463

87. Problem 37  p.463

88. Problem 38  p.464

89. Problem 43  p.464

90. Problem 45  p.465

5. Chapter 9

91. Example 1  p.470

92. Example 2  p.475

93. Example 3 ("from cancer"→"from bone cancer")  p.495

94. Example 5  p.498

95. Example 6  p.513

96. Example 7  p.515

97. Example 8  p.518

98. Example 10  p.525

99. Example 12  p.534

100. Example 13  p.535

II. Radiation Detection

101. If a disk type GM detector made of pressurized air (30 atm) with a radius of 2 cm,            thickness of 0.5 cm is placed 1 meter away from a point-like gamma source of energy          1 MeV as seen in the following figure.  [G. Knoll Chap 4. VI & VII]

(a)  What is the geometrical efficiency ?

(b)  If the attenuation coefficient of the gas at 1 atm in the gamma-ray energy of 1                 MeV in the problem is 0.02  [1/cm/atm] , then what is the interaction efficiency ?

If the measured count for 10 min is 54,580 and the GM detector dead time is 1                msec, what is the incident rate [1/sec] of gamma ray in the detector ?  Hint, GM              detector follows the non-paralyzable dead-time system. n=m/(1-mt )

102. If the spectrum of radiation sample in a simple gas counter set-up is given as below,          sketch the counting curve (a count rate as a function of bias voltage)  [G. Knoll Chap          4. IV]

103. The following figure is an idealized pulse height spectrum of a high mono-energetic            gamma-ray source by a HP detector. Explain the origins of the five features (a to e)           of the spectrum. [G. Knoll Chap 10. II & III]

104. A student measured a gamma-ray check source by the above HP Ge detector in a             laboratory. Answer the following questions when the data obtained was given in the            following table. [G. Knoll Chap 3. IV]

(a) Calculate the activity of the source in Bq. Consider the total counting efficiency           and the background.

(b) Calculate the uncertainty of the activity in Bq for the answer of the above                question.

Condition	Counts	Meas. Time (sec)
With Source	360,505	60
Background	38,192	60

105. A radioactive source was measured with GM counter having the absolute efficiency of          2 %. The measured activity was 72,000 counts for 2 min and the background was              14,400 counts for 1 min. What is the source activity and its error in Bq units ? [G.            Knoll Chap 3. IV]

106. Explain the differences of operation principles and applications for three types of gas           detectors; an ionization chamber, a proportional counter, a GM counter. [G. Knoll               Chap 6. I]

107. Explain the dead time, resolving time and recovery time of a Geiger Muller counter            using a figure of pulses in time. [G. Knoll Chap 7. IV]

108. Typical counting system can be assembled with several signal processing components          and a sensor. Draw a black box diagram for a typical counting system with the                 following components; A sensor, A timer, A counter, A Discriminator, A preamplifier, A          linear amplifier, A high voltage power supply. [G. Knoll Chap 17. VI]

109. Compare the advantages and disadvantages between a NaI(Tl) scintillation detector and          a HPGe detector in terms of the detection efficiency and the energy resolution.

110. Isotope of Boron-10 is used for neutron detector as (1) BF3 gas or (2) Boron-lined            P10 gas proportional counters.   We can assume the following reaction as a neutron            conversion process for thermal neutron detection. [G. Knoll Chap 14. II]

[eqn: n`+` ^{10} B`` -> ` ^{7} Li`+` alpha ```````(94%)`````````Q=2.310`[MeV]]

(a) Estimate the kinetic energy of Li-7 and alpha particles in MeV.

(b) Draw the spectrum of BF3 gas proportional counter and explain the 3 components          of spectrum

(c) Draw the spectrum of B-lined gas proportional counter and explain the 2                  components of spectrum

III. Materials

111. There are several ways to strengthen the metals and alloys, such as grain size             control, cold working, solid solution hardening, and dispersion hardening.

(a) Explain how the metals and alloys are strengthened by cold working.

(b) Precipitation hardening is one of the dispersion hardening mechanisms. What are      the required characteristics of the precipitates to achieve the significant hardening?

112. Explain the following aging mechanisms of the structural materials used in the              commercial water reactors. Also explain, if any, the mitigative or remedial actions to       prevent or slow down the progress of each aging mechanism.

(a) Irradiation embrittlement of the reactor pressure vessel steels.

(b) Stress corrosion cracking of the steam generator tube materials.

113. Explain the following aging mechanisms of the structural materials used in the              commercial water reactors. Also explain, if any, the mitigative or remedial actions to       prevent or slow down the progress of each aging mechanism.

(a) Flow accelerated corrosion of the secondary piping materials.

(b) Dimensional change of a CANDU pressure tube materials.

114. Answer the followings;

(a) List and briefly explain strengthening mechanisms of metals and alloys.

(b) Shown below is the Fe-rich portion of the Fe-C phase diagram. Mark the               eutectic and eutectoid points on the plot and write down the reactions.

115. Stainless steels are widely used as structural materials in nuclear power plants. One        of such stainless steel is a type SS304 whose typical composition is Fe-18Cr-8Ni         with about 0.06% of carbon.

(a) Explain the role of each element (Fe, Cr, Ni, C) in terms of phase stability and         corrosion resistance.

(b) Stainless steels can be sensitized during heat treatment or welding process.             Explain how the sensitization happens.

116. Austenitic stainless steels, such as SS304, SS316 are widely used as structural             materials in nuclear power plants. They are known to be susceptible to sensitization       during welding process.

(a) Explain how the sensitization happens during welding process

(b) How would you do to prevent sensitization of 304 SS during welding? Please            focus on the role of carbon in your explanation.

117. If a zinc surface is corroding at a current density of 3.45*10-7 A/cm2, what thickness       of metal will be corroded in 210 days? (Atomic weight of Zn : 65.38 g/mol.  Density        of Zn :   7.133 g/cm3)

118. Consider the ductile fracture processes of the round bar tensile specimen under             tensile loading. Assume the brittle inclusions are dispersed within the specimens.

(a) Explain and schematically draw the formation of initial crack.

(b) Explain and schematically draw the propagation of crack.

(c) Explain and schematically draw the final fracture.

119. Shown bellow are the mechanical properties changes of a precipitation hardening

nickel-base superalloy and Ti3Al intermetallics. Discuss the followings:

(a) What are the advantages and disadvantages of nickel-base supperalloys in high          temperature application.

(b) Repeat a) for Ti3Al intermetallics.

(c) Why the nickel-base superalloy loses strength above ~600C.

(d) What would be the proper choice of strengthening mechanism if the nickel-base         alloys are to be used over 600C?

120. It is known that the material properties are gradually affected by the fast neutron

irradiation during the reactor operation. The degree of fast neutron irradiation is          measured as dpa (displacement per atom).

(a) From the elastic scattering of fast neutron with atom nucleus, calculate the             maximum and average energy transfer to Fe (M = 56 amu, aniostropy correction       factor f = 0.57)

(b) Calculate the dpa/days when 2 MeV fast neutrons (flux = 1*1015/cm2-sec) are         irradiated on Fe atoms. Assume displacement cross-section (sd) is equal to elastic      scattering cross-section (sel = 3 barns)

IV. Fuel Cycles

121.  Define or describe the following terms or concepts:

(a) crud, (b) radiolysis of water, (c) accelerator transmutation of waste, (d) PUREX             process, (e) pyroprocessing, (f) LLW, (g) TRU, (h) HLW, (i) SNF, and (j) back-end              fuel cycle

122. Define or describe the following terms or concepts:

(a) yellowcake, (b) orange oxide, and (c) green salt

(d) Write balanced chemical equations for three different methods to produce metallic               uranium.

123. Describe the following chemical reactions:

(a) UCl6 is also volatile similar to UF6. Why is UCl6 inappropriate for the enrichment                of uranium?

(b) Even though UO2 can be converted directly to UF6, why is it first converted to                 UF4 and then to UF6? And write the chemical reactions from UO2 through UF4 as               intermediate product to UF6.

(c) Nitric acid readily dissolves UO2. Why doesn't hydrochloric acid?

124. Natural uranium is 0.72 atom % [eqn: {} _{92} ^{235} U``], and the fuel used in light water reactors is              typically 3 - 5 atom % [eqn: {} _{92} ^{235} U``]. This means the refined uranium must be enriched in the           lighter 235 isotope prior to fuel fabrication. Describe the following enrichment                  techniques: (a) gaseous diffusion, (b) gas centrifuges, (c) electromagnetic separation,            and (d) laser enrichment. (e) What is the theoretical maximum separation factor for             separation by gaseous diffusion of  [eqn: {} _{2} ^{3} H``e] and [eqn: {} _{2} ^{4} He``]? (f) If a gaseous diffusion plant              produces uranium (UF6) with a 235/238 ratio of 5, what is the expected 234/235 ratio           in the resulting material?

125. Discuss the disposal of the following examples of radioactive wastes:

(a) Water solutions containing 1 mCi of [eqn: {} _{1} ^{3} H``] from a research lab (4 points)

(b) Gas escaping from the dissolution of 1 kg of irradiated reactor fuel (3 points)

(c) Ion exchange resin used to purify the cooling water of a 1-MW research reactor                (4 points)

126. Describe the front-end fuel cycle and the back-end fuel cycle and explain various              physical and chemical processes in each fuel cycle step with pictorial flow sheet.

127. Of all the radiation-chemical reactions that have been studied in aqueous solution, the           most important is the decomposition of pure water itself. This is called the radiolysis           of water which results in a large variety of chemical changes. Therefore it draws              interests in various fields of reactor chemistry, nuclear fuel cycle, nuclear waste                disposal, and biology.

(a) Write the governing reactions of the water radiolysis and describe its intermediate              products and final products. (5 points)

(b) Given a G-value of 1.59 for the production of hydrogen gas by the irradiation of               TBP (tributyl phosphate) with 1-MeV electrons, calculate the rate of hydrogen gas              evolution in a liter of TBP irradiated for 1 h at a dose rate of 200 W/liter. Assume              the standard conditions for temperature and pressure. (5 points)

128. In an UO2 fueled reactor, the transuranium elements are produced in the course of             nuclear reactions. Describe the generating nuclear reaction mechanism of the                   transuranic elements (Np, Pu, Am, Cm), and how much of each transuranic element is           approximately produced in spent nuclear fuel, although it depends on the burn-up of            nuclear fuel ?

129. By 1955, scientists at Berkeley had prepared an equilibrium amount of about 109               atoms of [eqn: {} _{```99} ^{253} Es``]by neutron irradiation of plutonium in The Materials Testing Reactor in           Idaho. They thought it might be possible to prepare element 101 using the reaction

[eqn: {} _{```99} ^{253} Es```+` _{``2} ^{``4} He`` -> ` _{``101} ^{`256} Md```+` _{``0} ^{``1} n````]

How many atoms of the element 101 are produced under the following conditions               below?

(Use: s is the reaction cross section (10-27cm2), f is the helium ion flux                         (1014particles/s), l is the decay constant of [eqn: {} _{```99} ^{253} Es``] (10-4s-1), and t is the length of               each bombardment (104 s)

130. The favored method for permanent storage of radioactive waste is deep geologic                repositories. This option is the only option for unprocessed spent fuel assemblies               and for most high level waste. The prevailing design strategy for waste repositories            is that of multiple barriers. What is the multi-barrier system in a deep geologic                 repository? Define each barrier and describe its technical roles.

131. Discuss advantages and disadvantages of the Th-U fuel cycle and the U-Pu fuel               cycle from the perspective of the fuel reprocess and the yield of long-lived isotopes           and explain why [eqn: {} _{90} ^{228} Th``] and [eqn: {} _{92} ^{232} U``]are a nuisance in the thorium-uranium fuel cycle.

132. Fuel reprocessing has three objectives: (a) to recover U or Pu from the spent fuel             for reuse as a nuclear reactor fuel or to render the waste less hazardous, (b) to               remove fission products from the actinides to lessen short-term radioactivity                    problems, and (c) to convert the radioactive waste into a safe form for storage. The            hydro-metallurgical process, PUREX process, is used for almost all fuel reprocessing           today. An alternative to the aqueous separation process, "dry" process, called                   pyroprocess, has also been studied, but none has been used on an industrial scale.             Describe both processes and discuss advantages and disadvantages.

133. Consider transmutation of plutonium 239 by a light water reactor. We assume that              fresh fuel initially contains N28 atoms of 238U and N29 atoms of 239Pu. To simplify,             we assume that the fresh fuel contains no 235U. We also neglect the production of              239Pu in the core by absorption of resonance neutrons in 238U. Plutonium 239,                   therefore, is generated only by thermal neutron capture by 238U and consumed by its           fission. Assume that the thermal flux fM is constant with time and uniform in the core.           The number, N28, of 238U atoms is assumed to be constant with time. The absorption           cross section of 239Pu is σ29. The absorption cross section of 238U is σ28. t is time.

(a) Write the governing equation and the initial condition for the number, N49(t), of                 239Pu atoms in the reactor core. Solve the equation. (4 points)

(b) Define and formulate the burn-up for this system in terms of the parameters in                 this model. (3 points)

(c) To avoid breeding of 239Pu in the fuel (i.e., to keep the number of atoms of 239Pu               always smaller than N29 (3 points)

134. Consider extraction of UO22+ in the aqueous phase by the organic solvent TBP by the           following equilibrium:

[eqn: UO _{2} ^{2+} `(aq)``+`2NO _{3} ^{-} (aq)+2TBP(org)`` LRARROW ``UO _{2} (NO _{3} ) _{2} BULLET 2TBP(org)]

(a) Write the equilibrium constant KUO2 in terms of the concentrations of the species                appearing in the above reaction. (3 points)

(b) Write the definition of the distribution coefficient DUO2 for UO22+. (3 points)

(c) Assume that the concentration of total TBP, both combined and uncombined, in the              organic phase is C. Obtain the equation for the distribution coefficient DUO2 for                  UO22+ in terms of C, DUO2 and aqueous concentrations. Assume DUO2 = 12, C = 1.5              mol/liter, and [NO3-] = 3 mol/liter. Would DUO2 increase or decrease if NO3- of the              aqueous phase increase? (4 points)

135. Answer the following questions

(a) How and where is 14C generated in a nuclear fuel cycle? Why is this nuclide of                 concern in the waste management? (2.5 points)

(b) Select a radionuclide (other than 14C) that is important in radioactive waste                      management for nuclear fuel cycle. Discuss how and where mainly that nuclide is               generated in the fuel cycle, and explain why that nuclide is so important. (2.5                  points)

(c) Answer the following true/false questions. Explain briefly your answer. (each 1                 point)

(c-1) Radioactivity of any radionuclide in spent fuel from a PWR	decreases monotonically with time after it is discharged from a reactor.

(c-2) Because wastes from reactor decommissioning are mostly concrete	and

structural materials	consisting of reactor buildings, decommissioning

wastes can be regarded as non-radioactive.

(c-3) With careful choice of solvents and operating conditions, perfect

separation of one material from another is possible by a multi-stage

solvent-solvent extraction process.

(c-4) All fission-product isotopes in a spent fuel at discharge from a	reactor

core are radioactive.

(c-5) Radionuclides included in activated materials are so short-lived that	these

can be regarded as non-radioactive after a storage period of 10 y.

136. In a radioactive decay chain

[eqn: A```` REL -> {lambda _{1}} {} `````B````` REL -> {lambda _{2}} {} `````C````(stable)]

(a) A sample of pure A nucleus is isolated at time zero. Derive a general expression               for the time at which the daughter's (B) activity is a maximum and the raio of                  daughter activity at that time to initial parent activity

(b) Explain the transient and secular radioactive equilibrium and give the conditions

137. Calculate the time required for preprocessing cooling of irradiated fuel such that the             inhalation toxicity (C) of the contained 131I will have decayed to that of 129I. Assume            235U fission at constant power and an irradiation time of 3 years. Use the following             data.

	T1/2	Yield	C (in air, mCi/m3)
129I	1.7×107 yr	0.008	2×10-11
129I	8.05 d	0.0293	1×10-10

138. Consider a 1000 MWe PWR with

In-core inventory of coolant water = 8000 kg

Average thermal neutron flux = 3.5×1013 n/cm2·s

Capacity factor of the power plant = 0.8

(a) Calculate the tritium activity (Ci/yr) produced by D(n,g)T (T1/2 of tritium = 12.3 yr)               during the one calendar year. The corresponding effective cross section =                      3.35×10-4 b

(b) Assume water contains 0.015 a/o (atomic percent) D.

Assuming an average dissolved boron concentration of 1000 ppm in the coolant,                calculate the tritium activity (Ci/yr) produced yearly from the reaction in an                     average fast neutron flux 7×1013 n/cm2·s.

[eqn: {} ^{10} B```+`n`` -> ``2` ^{4} He``+``T`````( sigma =42`mb)]

Natural boron contains 19.61% of 10B.

139.

(a) Describe the radioactive materials existing inside the reactor coolant of PWR in                 terms of more than 4 different classes and list the important radionuclides in each              classes

(b) Describe various gaseous, liquid, and solid radioactive waste treatment systems                 with respect to treatment methods, system flow sheets, characteristics of the                   system and the important radionuclides in each system.

140. Pure 239Pu is placed in a reactor. How much 240Pu and 241Pu will be produced, when             50% of 239Pu is consumed? The thermal neutron flux is 1012 n/cm2·s.

[eqn: {} ^{241} Am`# ````````````````` NWARROW]

[eqn: {} ^{239} Pu```+`n````` -> `````` ^{240} Pu``` REL -> {n} {} ```` ^{241} Pu`````` REL -> {n} {}]

[eqn: ````````downarrow # fission]

The decay and neutron reaction data are:

	T1/2	l (s-1)	sc (barn)	sa (barn)
239Pu	24,400 yr		268.8	1011.3
240Pu	6,580 yr	3.34×10-12	289.5	289.5
241Pu	13.2 yr	1.66×10-9	368	1377

V. Engineering Mathematics

1. Chapter 2,3,8

141. 2-1 Exercise 21  p.44

142. 2-1 Exercise 25  p.44

143. 2-3 Example 5   p.56

144. 2-3 Exercise 17  p.58

145. 2-4 Example 1  p.62

146. 2-4 Exercise 27  p.65

147. 2-5 Example 2  p.68

148. 2-5 Exercise 19  p.70

149. 2-7 Example 2  p.76

150. 2-9 Exercise 1  p.98

151. 3-1 Exercise 15  p.115

152. 3-1 Exercise 23  p.115

153. 3-2 Example 1  p.117

154. 3-2 Exercise 1  p.118

155. 3-3 Example 4  p.122

156. 3-3 Exercise 17  p.124

157. 3-4 Example 2  p.128

158. 3-4 Example 10  p.133

159. 3-11 Example 2  p.186

160. 3-11 Exercise 3  p.188

161. 8-6 Example 7  p.391

162. 8-6 Exercise 57  p.395

163. 8-7 Example 1  p.397

164. 8-8 Example 4  p.401

165. 8-8 Exercise 15  p.403

166. 8-9 Example 1  p.406

167. 8-10 Example 3  p.412

168. 8-12 Example 2  p.425

169. 8-15 Example 2  p.441

170. 8-15 Exercise 1  p.442

2. Chapter 12,13,15

171. 12-1 Example 1  p.654

172. 12-1 Exercise 5  p.657

173. 12-2 Example 1  p.660

174. 12-2 Exercise 1  p.662

175. 12-2 Exercise 9  p.662

176. 12-3 Example 1  p.664

177. 12-3 Example 2  p.665

178. 12-3 Exercise 11  p.668

179. 12-4 Example 3  p.672

170. 12-4 Exercise 7  p.673

181. 13-1 Example 1  p.690

182. 13-1 Exercise 3  p.693

183. 13-2 Exercise 1  p.699

184. 13-2 Exercise 3  p.699

185. 13-3 Exercise 1  p.701

186. 13-3 Exercise 3  p.701

187. 13-4 Exercise 1  p.705

188. 13-4 Exercise 3  p.705

189. 13-5 Exercise 1  p.711

190. 13-8 Example 1  p.724

191. 15-2 Example 1  p.748

192. 15-2 Example 2  p.749

193. 15-2 Exercise 1  p.752

194. 15-2 Exercise 3  p.752

195. 15-3 Example 1  p.756

196. 15-3 Exercise 3  p.759

197. 15-4 Example 1  p.763

198. 15-4 Example 2  p.764

199. 15-4 Exercise 1  p.764

200. 15-4 Exercise 13  p.765