1
Answer to the questions of Chapter 4 No. 12--------------------------- Page 1
No. 13--------------------------- Page 2
No. 14--------------------------- Page 2
No. 17--------------------------- Page 3
No. 18--------------------------- Page 3
No. 24--------------------------- Page 4
No. 28--------------------------- Page 5
No. 33--------------------------- Page 6, 7
No. 49--------------------------- Page 8, 9
No. 61--------------------------- Page 10, 11, 12
2
3
4
5
6
7
8
9
10
11
12