Upload
doanhanh
View
248
Download
5
Embed Size (px)
Citation preview
BASICPROBABILITY
THEORY
Robert B. AshDepartment of Mathematics
University of Illinois
DOVER PUBLICATIONS, INC.Mineola, New York
46628-0 Ash 1 4/14/08 8:24 AM Page iii
Copyright
Copyright © 1970, 2008 by Robert B. AshAll rights reserved.
Bibliographical Note
This Dover edition, first published in 2008, is an unabridged republication ofthe work originally published in 1970 by John Wiley & Sons, Inc., New York.Readers of this book who would like to receive the solutions to the exercises notpublished in the book may request them from the publisher at the following e-mail address: [email protected]
Library of Congress Cataloging-in-Publication Data
Ash, Robert B.Basic propability theory / Robert B. Ash. — Dover ed.
p. cm.Includes index.Originally published: New York : Wiley, [1970]ISBN-13: 978-0-486-46628-6 ISBN-10: 0-486-46628-01. Probabilities. I. Title.
QA273.A77 2008519.2—dc22
200800473
Manufactured in the United States of AmericaDover Publications, Inc., 31 East 2nd Street, Mineola, N.Y. 11501
46628-0 Ash 1 4/14/08 8:24 AM Page iv
46628-0 Ash 1 4/14/08 8:24 AM Page v
46628-0 Ash 1 4/14/08 8:24 AM Page vi
46628-0 Ash 1 4/14/08 8:24 AM Page vii
46628-0 Ash 1 4/14/08 8:24 AM Page viii
46628-0 Ash 1 4/14/08 8:24 AM Page ix
46628-0 Ash 1 4/14/08 8:24 AM Page x
BASICPROBABILITY
THEORY
46628-0 Ash 1 4/14/08 8:24 AM Page xi
46628-0 Ash 1 4/14/08 8:24 AM Page xii
46628-0 Ash 1 4/14/08 8:24 AM Page 1
46628-0 Ash 1 4/14/08 8:24 AM Page 2
46628-0 Ash 1 4/14/08 8:24 AM Page 3
46628-0 Ash 1 4/14/08 8:24 AM Page 4
46628-0 Ash 1 4/14/08 8:24 AM Page 5
46628-0 Ash 1 4/14/08 8:24 AM Page 6
46628-0 Ash 1 4/14/08 8:24 AM Page 7
46628-0 Ash 1 4/14/08 8:24 AM Page 8
46628-0 Ash 1 4/14/08 8:24 AM Page 9
46628-0 Ash 1 4/14/08 8:24 AM Page 10
46628-0 Ash 1 4/14/08 8:24 AM Page 11
46628-0 Ash 1 4/14/08 8:24 AM Page 12
46628-0 Ash 1 4/14/08 8:24 AM Page 13
46628-0 Ash 1 4/14/08 8:24 AM Page 14
46628-0 Ash 1 4/14/08 8:24 AM Page 15
46628-0 Ash 1 4/14/08 8:24 AM Page 16
46628-0 Ash 1 4/14/08 8:24 AM Page 17
46628-0 Ash 1 4/14/08 8:24 AM Page 18
46628-0 Ash 1 4/14/08 8:24 AM Page 19
46628-0 Ash 1 4/14/08 8:24 AM Page 20
46628-0 Ash 1 4/14/08 8:24 AM Page 21
46628-0 Ash 1 4/14/08 8:24 AM Page 22
46628-0 Ash 1 4/14/08 8:24 AM Page 23
46628-0 Ash 1 4/14/08 8:24 AM Page 24
46628-0 Ash 1 4/14/08 8:24 AM Page 25
46628-0 Ash 1 4/14/08 8:24 AM Page 26
46628-0 Ash 1 4/14/08 8:24 AM Page 27
46628-0 Ash 1 4/14/08 8:24 AM Page 28
46628-0 Ash 1 4/14/08 8:24 AM Page 29
46628-0 Ash 1 4/14/08 8:24 AM Page 30
46628-0 Ash 1 4/14/08 8:24 AM Page 31
46628-0 Ash 1 4/14/08 8:24 AM Page 32
46628-0 Ash 1 4/14/08 8:24 AM Page 33
46628-0 Ash 1 4/14/08 8:24 AM Page 34
46628-0 Ash 1 4/14/08 8:24 AM Page 35
46628-0 Ash 1 4/14/08 8:24 AM Page 36
46628-0 Ash 1 4/14/08 8:24 AM Page 37
46628-0 Ash 1 4/14/08 8:24 AM Page 38
46628-0 Ash 1 4/14/08 8:24 AM Page 39
46628-0 Ash 1 4/14/08 8:24 AM Page 40
46628-0 Ash 1 4/14/08 8:24 AM Page 41
46628-0 Ash 1 4/14/08 8:24 AM Page 42
46628-0 Ash 1 4/14/08 8:24 AM Page 43
46628-0 Ash 1 4/14/08 8:24 AM Page 44
46628-0 Ash 1 4/14/08 8:25 AM Page 45
46628-0 Ash 1 4/14/08 8:25 AM Page 46
46628-0 Ash 1 4/14/08 8:25 AM Page 47
46628-0 Ash 1 4/14/08 8:25 AM Page 48
46628-0 Ash 1 4/14/08 8:25 AM Page 49
46628-0 Ash 1 4/14/08 8:25 AM Page 50
46628-0 Ash 1 4/14/08 8:25 AM Page 51
46628-0 Ash 1 4/14/08 8:25 AM Page 52
46628-0 Ash 1 4/14/08 8:25 AM Page 53
46628-0 Ash 1 4/14/08 8:25 AM Page 54
46628-0 Ash 1 4/14/08 8:25 AM Page 55
46628-0 Ash 1 4/14/08 8:25 AM Page 56
46628-0 Ash 1 4/14/08 8:25 AM Page 57
46628-0 Ash 1 4/14/08 8:25 AM Page 58
46628-0 Ash 1 4/14/08 8:25 AM Page 59
46628-0 Ash 1 4/14/08 8:25 AM Page 60
46628-0 Ash 1 4/14/08 8:25 AM Page 61
46628-0 Ash 1 4/14/08 8:25 AM Page 62
46628-0 Ash 1 4/14/08 8:25 AM Page 63
46628-0 Ash 1 4/14/08 8:25 AM Page 64
46628-0 Ash 1 4/14/08 8:25 AM Page 65
46628-0 Ash 1 4/14/08 8:25 AM Page 66
46628-0 Ash 1 4/14/08 8:25 AM Page 67
46628-0 Ash 1 4/14/08 8:25 AM Page 68
46628-0 Ash 1 4/14/08 8:25 AM Page 69
46628-0 Ash 1 4/14/08 8:25 AM Page 70
46628-0 Ash 1 4/14/08 8:25 AM Page 71
46628-0 Ash 1 4/14/08 8:25 AM Page 72
46628-0 Ash 1 4/14/08 8:25 AM Page 73
46628-0 Ash 1 4/14/08 8:25 AM Page 74
46628-0 Ash 1 4/14/08 8:25 AM Page 75
46628-0 Ash 1 4/14/08 8:25 AM Page 76
46628-0 Ash 1 4/14/08 8:25 AM Page 77
46628-0 Ash 1 4/14/08 8:25 AM Page 78
46628-0 Ash 1 4/14/08 8:25 AM Page 79
46628-0 Ash 1 4/14/08 8:25 AM Page 80
46628-0 Ash 1 4/14/08 8:25 AM Page 81
46628-0 Ash 1 4/14/08 8:25 AM Page 82
46628-0 Ash 1 4/14/08 8:25 AM Page 83
46628-0 Ash 1 4/14/08 8:25 AM Page 84
46628-0 Ash 1 4/14/08 8:25 AM Page 85
46628-0 Ash 1 4/14/08 8:25 AM Page 86
46628-0 Ash 1 4/14/08 8:25 AM Page 87
46628-0 Ash 1 4/14/08 8:25 AM Page 88
46628-0 Ash 1 4/14/08 8:25 AM Page 89
46628-0 Ash 1 4/14/08 8:25 AM Page 90
46628-0 Ash 1 4/14/08 8:25 AM Page 91
46628-0 Ash 1 4/14/08 8:25 AM Page 92
46628-0 Ash 1 4/14/08 8:25 AM Page 93
46628-0 Ash 1 4/14/08 8:25 AM Page 94
46628-0 Ash 1 4/14/08 8:25 AM Page 95
46628-0 Ash 1 4/14/08 8:25 AM Page 96
46628-0 Ash 1 4/14/08 8:25 AM Page 97
46628-0 Ash 1 4/14/08 8:25 AM Page 98
46628-0 Ash 1 4/14/08 8:25 AM Page 99
46628-0 Ash 1 4/14/08 8:25 AM Page 100
46628-0 Ash 1 4/14/08 8:25 AM Page 101
46628-0 Ash 1 4/14/08 8:25 AM Page 102
46628-0 Ash 1 4/14/08 8:25 AM Page 103
46628-0 Ash 1 4/14/08 8:25 AM Page 104
46628-0 Ash 1 4/14/08 8:25 AM Page 105
46628-0 Ash 1 4/14/08 8:25 AM Page 106
46628-0 Ash 1 4/14/08 8:25 AM Page 107
46628-0 Ash 1 4/14/08 8:25 AM Page 108
46628-0 Ash 1 4/14/08 8:25 AM Page 109
46628-0 Ash 1 4/14/08 8:25 AM Page 110
46628-0 Ash 1 4/14/08 8:25 AM Page 111
46628-0 Ash 1 4/14/08 8:25 AM Page 112
46628-0 Ash 1 4/14/08 8:25 AM Page 113
46628-0 Ash 1 4/14/08 8:25 AM Page 114
46628-0 Ash 1 4/14/08 8:25 AM Page 115
46628-0 Ash 1 4/14/08 8:25 AM Page 116
46628-0 Ash 1 4/14/08 8:25 AM Page 117
46628-0 Ash 1 4/14/08 8:25 AM Page 118
46628-0 Ash 1 4/14/08 8:25 AM Page 119
46628-0 Ash 1 4/14/08 8:25 AM Page 120
46628-0 Ash 1 4/14/08 8:25 AM Page 121
46628-0 Ash 1 4/14/08 8:25 AM Page 122
46628-0 Ash 1 4/14/08 8:25 AM Page 123
46628-0 Ash 1 4/14/08 8:25 AM Page 124
46628-0 Ash 1 4/14/08 8:25 AM Page 125
46628-0 Ash 1 4/14/08 8:25 AM Page 126
46628-0 Ash 1 4/14/08 8:25 AM Page 127
46628-0 Ash 1 4/14/08 8:25 AM Page 128
46628-0 Ash 1 4/14/08 8:25 AM Page 129
46628-0 Ash 1 4/14/08 8:25 AM Page 130
46628-0 Ash 1 4/14/08 8:25 AM Page 131
46628-0 Ash 1 4/14/08 8:25 AM Page 132
46628-0 Ash 1 4/14/08 8:25 AM Page 133
46628-0 Ash 1 4/14/08 8:25 AM Page 134
46628-0 Ash 1 4/14/08 8:25 AM Page 135
46628-0 Ash 1 4/14/08 8:25 AM Page 136
46628-0 Ash 1 4/14/08 8:25 AM Page 137
46628-0 Ash 1 4/14/08 8:25 AM Page 138
46628-0 Ash 1 4/14/08 8:25 AM Page 139
46628-0 Ash 1 4/14/08 8:25 AM Page 140
46628-0 Ash 1 4/14/08 8:25 AM Page 141
46628-0 Ash 1 4/14/08 8:25 AM Page 142
46628-0 Ash 1 4/14/08 8:26 AM Page 143
46628-0 Ash 1 4/14/08 8:26 AM Page 144
46628-0 Ash 1 4/14/08 8:26 AM Page 145
46628-0 Ash 1 4/14/08 8:26 AM Page 146
46628-0 Ash 1 4/14/08 8:26 AM Page 147
46628-0 Ash 1 4/14/08 8:26 AM Page 148
46628-0 Ash 1 4/14/08 8:26 AM Page 149
46628-0 Ash 1 4/14/08 8:26 AM Page 150
46628-0 Ash 1 4/14/08 8:26 AM Page 151
46628-0 Ash 1 4/14/08 8:26 AM Page 152
46628-0 Ash 1 4/14/08 8:26 AM Page 153
46628-0 Ash 1 4/14/08 8:26 AM Page 154
46628-0 Ash 1 4/14/08 8:26 AM Page 155
46628-0 Ash 1 4/14/08 8:26 AM Page 156
46628-0 Ash 1 4/14/08 8:26 AM Page 157
46628-0 Ash 1 4/14/08 8:26 AM Page 158
46628-0 Ash 1 4/14/08 8:26 AM Page 159
46628-0 Ash 1 4/14/08 8:26 AM Page 160
46628-0 Ash 1 4/14/08 8:26 AM Page 161
46628-0 Ash 1 4/14/08 8:26 AM Page 162
46628-0 Ash 1 4/14/08 8:26 AM Page 163
46628-0 Ash 1 4/14/08 8:26 AM Page 164
46628-0 Ash 1 4/14/08 8:26 AM Page 165
46628-0 Ash 1 4/14/08 8:26 AM Page 166
46628-0 Ash 1 4/14/08 8:26 AM Page 167
46628-0 Ash 1 4/14/08 8:26 AM Page 168
46628-0 Ash 1 4/14/08 8:26 AM Page 169
46628-0 Ash 1 4/14/08 8:26 AM Page 170
46628-0 Ash 1 4/14/08 8:26 AM Page 171
46628-0 Ash 1 4/14/08 8:26 AM Page 172
46628-0 Ash 1 4/14/08 8:26 AM Page 173
46628-0 Ash 1 4/14/08 8:26 AM Page 174
46628-0 Ash 1 4/14/08 8:26 AM Page 175
46628-0 Ash 1 4/14/08 8:26 AM Page 176
46628-0 Ash 1 4/14/08 8:26 AM Page 177
46628-0 Ash 1 4/14/08 8:26 AM Page 178
46628-0 Ash 1 4/14/08 8:26 AM Page 179
46628-0 Ash 1 4/14/08 8:26 AM Page 180
46628-0 Ash 1 4/14/08 8:26 AM Page 181
46628-0 Ash 1 4/14/08 8:26 AM Page 182
46628-0 Ash 1 4/14/08 8:26 AM Page 183
46628-0 Ash 1 4/14/08 8:26 AM Page 184
46628-0 Ash 1 4/14/08 8:26 AM Page 185
46628-0 Ash 1 4/14/08 8:26 AM Page 186
46628-0 Ash 1 4/14/08 8:26 AM Page 187
46628-0 Ash 1 4/14/08 8:26 AM Page 188
46628-0 Ash 1 4/14/08 8:26 AM Page 189
46628-0 Ash 1 4/14/08 8:26 AM Page 190
46628-0 Ash 1 4/14/08 8:26 AM Page 191
46628-0 Ash 1 4/14/08 8:26 AM Page 192
46628-0 Ash 1 4/14/08 8:26 AM Page 193
46628-0 Ash 1 4/14/08 8:26 AM Page 194
46628-0 Ash 1 4/14/08 8:26 AM Page 195
46628-0 Ash 1 4/14/08 8:26 AM Page 196
46628-0 Ash 1 4/14/08 8:26 AM Page 197
46628-0 Ash 1 4/14/08 8:26 AM Page 198
46628-0 Ash 1 4/14/08 8:26 AM Page 199
46628-0 Ash 1 4/14/08 8:26 AM Page 200
46628-0 Ash 2 4/14/08 8:31 AM Page 201
46628-0 Ash 2 4/14/08 8:31 AM Page 202
46628-0 Ash 2 4/14/08 8:31 AM Page 203
46628-0 Ash 2 4/14/08 8:31 AM Page 204
46628-0 Ash 2 4/14/08 8:31 AM Page 205
46628-0 Ash 2 4/14/08 8:31 AM Page 206
46628-0 Ash 2 4/14/08 8:31 AM Page 207
46628-0 Ash 2 4/14/08 8:31 AM Page 208
46628-0 Ash 2 4/14/08 8:31 AM Page 209
46628-0 Ash 2 4/14/08 8:31 AM Page 210
46628-0 Ash 2 4/14/08 8:31 AM Page 211
46628-0 Ash 2 4/14/08 8:31 AM Page 212
46628-0 Ash 2 4/14/08 8:31 AM Page 213
46628-0 Ash 2 4/14/08 8:31 AM Page 214
46628-0 Ash 2 4/14/08 8:31 AM Page 215
46628-0 Ash 2 4/14/08 8:31 AM Page 216
46628-0 Ash 2 4/14/08 8:31 AM Page 217
46628-0 Ash 2 4/14/08 8:31 AM Page 218
46628-0 Ash 2 4/14/08 8:31 AM Page 219
46628-0 Ash 2 4/14/08 8:31 AM Page 220
46628-0 Ash 2 4/14/08 8:31 AM Page 221
46628-0 Ash 2 4/14/08 8:31 AM Page 222
46628-0 Ash 2 4/14/08 8:31 AM Page 223
46628-0 Ash 2 4/14/08 8:31 AM Page 224
46628-0 Ash 2 4/14/08 8:31 AM Page 225
46628-0 Ash 2 4/14/08 8:31 AM Page 226
46628-0 Ash 2 4/14/08 8:31 AM Page 227
46628-0 Ash 2 4/14/08 8:31 AM Page 228
46628-0 Ash 2 4/14/08 8:31 AM Page 229
46628-0 Ash 2 4/14/08 8:31 AM Page 230
46628-0 Ash 2 4/14/08 8:31 AM Page 231
46628-0 Ash 2 4/14/08 8:31 AM Page 232
46628-0 Ash 2 4/14/08 8:31 AM Page 233
46628-0 Ash 2 4/14/08 8:31 AM Page 234
46628-0 Ash 2 4/14/08 8:31 AM Page 235
46628-0 Ash 2 4/14/08 8:31 AM Page 236
46628-0 Ash 2 4/14/08 8:31 AM Page 237
46628-0 Ash 2 4/14/08 8:31 AM Page 238
46628-0 Ash 2 4/14/08 8:31 AM Page 239
46628-0 Ash 2 4/14/08 8:31 AM Page 240
46628-0 Ash 2 4/14/08 8:31 AM Page 241
46628-0 Ash 2 4/14/08 8:31 AM Page 242
46628-0 Ash 2 4/14/08 8:31 AM Page 243
46628-0 Ash 2 4/14/08 8:31 AM Page 244
46628-0 Ash 2 4/14/08 8:31 AM Page 245
46628-0 Ash 2 4/14/08 8:31 AM Page 246
46628-0 Ash 2 4/14/08 8:31 AM Page 247
46628-0 Ash 2 4/14/08 8:31 AM Page 248
46628-0 Ash 2 4/14/08 8:31 AM Page 249
46628-0 Ash 2 4/14/08 8:31 AM Page 250
46628-0 Ash 2 4/14/08 8:31 AM Page 251
46628-0 Ash 2 4/14/08 8:31 AM Page 252
46628-0 Ash 2 4/14/08 8:31 AM Page 253
46628-0 Ash 2 4/14/08 8:31 AM Page 254
46628-0 Ash 2 4/14/08 8:31 AM Page 255
46628-0 Ash 2 4/14/08 8:31 AM Page 256
46628-0 Ash 2 4/14/08 8:31 AM Page 257
46628-0 Ash 2 4/14/08 8:31 AM Page 258
46628-0 Ash 2 4/14/08 8:31 AM Page 259
46628-0 Ash 2 4/14/08 8:31 AM Page 260
46628-0 Ash 2 4/14/08 8:31 AM Page 261
46628-0 Ash 2 4/14/08 8:31 AM Page 262
46628-0 Ash 2 4/14/08 8:31 AM Page 263
46628-0 Ash 2 4/14/08 8:31 AM Page 264
46628-0 Ash 2 4/14/08 8:31 AM Page 265
46628-0 Ash 2 4/14/08 8:31 AM Page 266
46628-0 Ash 2 4/14/08 8:31 AM Page 267
46628-0 Ash 2 4/14/08 8:31 AM Page 268
46628-0 Ash 2 4/14/08 8:31 AM Page 269
46628-0 Ash 2 4/14/08 8:31 AM Page 270
46628-0 Ash 2 4/14/08 8:31 AM Page 271
46628-0 Ash 2 4/14/08 8:31 AM Page 272
46628-0 Ash 2 4/14/08 8:31 AM Page 273
46628-0 Ash 2 4/14/08 8:31 AM Page 274
46628-0 Ash 2 4/14/08 8:31 AM Page 275
46628-0 Ash 2 4/14/08 8:31 AM Page 276
46628-0 Ash 2 4/14/08 8:31 AM Page 277
46628-0 Ash 2 4/14/08 8:31 AM Page 278
46628-0 Ash 2 4/14/08 8:31 AM Page 279
46628-0 Ash 2 4/14/08 8:31 AM Page 280
46628-0 Ash 2 4/14/08 8:31 AM Page 281
46628-0 Ash 2 4/14/08 8:31 AM Page 282
46628-0 Ash 2 4/14/08 8:31 AM Page 283
46628-0 Ash 2 4/14/08 8:31 AM Page 284
46628-0 Ash 2 4/14/08 8:31 AM Page 285
46628-0 Ash 2 4/14/08 8:31 AM Page 286
46628-0 Ash 2 4/14/08 8:31 AM Page 287
46628-0 Ash 2 4/14/08 8:31 AM Page 288
46628-0 Ash 2 4/14/08 8:31 AM Page 289
46628-0 Ash 2 4/14/08 8:31 AM Page 290
46628-0 Ash 2 4/14/08 8:31 AM Page 291
46628-0 Ash 2 4/14/08 8:31 AM Page 292
46628-0 Ash 2 4/14/08 8:31 AM Page 293
46628-0 Ash 2 4/14/08 8:31 AM Page 294
46628-0 Ash 2 4/14/08 8:31 AM Page 295
46628-0 Ash 2 4/14/08 8:32 AM Page 296
46628-0 Ash 2 4/14/08 8:32 AM Page 297
46628-0 Ash 2 4/14/08 8:32 AM Page 298
46628-0 Ash 2 4/14/08 8:32 AM Page 299
46628-0 Ash 2 4/14/08 8:32 AM Page 300
46628-0 Ash 2 4/14/08 8:32 AM Page 301
46628-0 Ash 2 4/14/08 8:32 AM Page 302
46628-0 Ash 2 4/14/08 8:32 AM Page 303
46628-0 Ash 2 4/14/08 8:32 AM Page 304
46628-0 Ash 2 4/14/08 8:32 AM Page 305
46628-0 Ash 2 4/14/08 8:32 AM Page 306
46628-0 Ash 2 4/14/08 8:32 AM Page 307
46628-0 Ash 2 4/14/08 8:32 AM Page 308
46628-0 Ash 2 4/14/08 8:32 AM Page 309
46628-0 Ash 2 4/14/08 8:32 AM Page 310
46628-0 Ash 2 4/14/08 8:32 AM Page 311
46628-0 Ash 2 4/14/08 8:32 AM Page 312
46628-0 Ash 2 4/14/08 8:32 AM Page 313
46628-0 Ash 2 4/14/08 8:32 AM Page 314
46628-0 Ash 2 4/14/08 8:32 AM Page 315
46628-0 Ash 2 4/14/08 8:32 AM Page 316
46628-0 Ash 2 4/14/08 8:32 AM Page 317
46628-0 Ash 2 4/14/08 8:32 AM Page 318
46628-0 Ash 2 4/14/08 8:32 AM Page 319
46628-0 Ash 2 4/14/08 8:32 AM Page 320
46628-0 Ash 2 4/14/08 8:32 AM Page 321
46628-0 Ash 2 4/14/08 8:32 AM Page 322
46628-0 Ash 2 4/14/08 8:32 AM Page 323
46628-0 Ash 2 4/14/08 8:32 AM Page 324
46628-0 Ash 2 4/14/08 8:32 AM Page 325
46628-0 Ash 2 4/14/08 8:32 AM Page 326
46628-0 Ash 2 4/14/08 8:32 AM Page 327
46628-0 Ash 2 4/14/08 8:32 AM Page 328
46628-0 Ash 2 4/14/08 8:32 AM Page 329
46628-0 Ash 2 4/14/08 8:32 AM Page 330
46628-0 Ash 2 4/14/08 8:32 AM Page 331
46628-0 Ash 2 4/14/08 8:32 AM Page 332
46628-0 Ash 2 4/14/08 8:32 AM Page 333
46628-0 Ash 2 4/14/08 8:32 AM Page 334
46628-0 Ash 2 4/14/08 8:32 AM Page 335
46628-0 Ash 2 4/14/08 8:32 AM Page 336
46628-0 Ash 2 4/14/08 8:32 AM Page 337
46628-0 Ash 2 4/14/08 8:32 AM Page 338
46628-0 Ash 2 4/14/08 8:32 AM Page 339
46628-0 Ash 2 4/14/08 8:32 AM Page 340