There are 8 letters and corresponding 8 envelopes. If 8 letters are placed into 8 envelopes randomly, find the number of ways that exactly one letter is placed into wrong envelope.	Choose one
A) 0	B) 1	C) 2	D) 3	E) 4
in 8 letter one letter is placed into wrong envelop means balance 7 are in correct place. so all 7 letters are in correct place means definitely the remaining 8th one is also placed correctly. so ans is 0   0NSWER:0
<result>A</result>
There are 8 letters and corresponding 8 envelopes. If 8 letters are placed into 8 envelopes randomly, find the number of ways that exactly one letter is placed into wrong envelope.