Let X represent the time it takes from when someone enters the line for a roller coaster until they exit on the other side. Consider the probability model defined by the cumulative distribution...

Let X represent the time it takes from when someone enters the line for a roller coaster until they exit on the other side. Consider the probability model defined by the cumulative distribution function given below.

a) What is E(x)? Give answer to three decimal places.

b) What is the value
c
such that P(X <= c)="0.28?" give="" your="" answer="" to="" four="" decimal="">

c) What is the probability that X falls within 0.31 minutes of its mean? Give your answer to four decimal places.