100 metres of fencing are available to enclose a rectangular pen. The area, A square metres, enclosed is given by A = 25x - x^2 where the length of the pen is x metres,
a) What is maximum area that can be enclosed?
b) What are the dimensions of the pen with maximum area?

The length of time it takes to find a parking space at 9 a.m. follows a normal distribution with a mean of 5 minutes and a standard deviation of 2 minutes. find the probability that it takes at least 8 minutes to find a parking space. (round your answer to four decimal places.)