Nine people are on an elevator that stops at exactly 9 floors. What is the probability that exactly one person will push the button for each floor?  Answers:	A) 9!/9^9	B) 9^9/9!	C) 9/9!	D) 9/9^9	E) 1/9^9
Each person out of 9 has 9 options, hence total # of outcomes is 9^9;   Favorable outcomes will be 9!, which is # of ways to assign 9 different buttons to 9 people   So basically # of arrangements of 9 distinct objects: 9!.   P=favorable/total=9!/9^9   9!/9^9nswer: 9!/9^9.
<result>A</result>
Nine people are on an elevator that stops at exactly 9 floors. What is the probability that exactly one person will push the button for each floor?