6.40

A.

4 * 16 * 16

B.

first loop, same like 6.38, but

write count is 16*16, miss rate is 1/2.

second loop, same like 6.39, but

write count is 16163, miss rate is 1/6.

miss count is

16161/2 + 16163*1/6

C.

1/4