I desperately need a math genius.. statistic problem ?

Question

1.) the waiting time, in hours, between sucessive speeders spotted by a radar unit is a continuos random variable with cumulative distribution function

F(x)={0 x<0,

1-e^-8x, x>0.

find the probability of waitng less than 12 minutes between sucessive speeders

a. using the cumulative distribution function of X;

b. using the probability density function of X.

Answer 1

e=mc2