I need help with this question

The life l 1' 'i 1 in years) of a certain machine is a random variable with probability density function dened by f(x) = - [2 + } for x in [9, 16]. 16 J; .m- A. Find the mean life of this machine. _'| BR The mean life is approximately [1 years. (Round to two decimal places as needed.) 8. Find the standard deviation of the distribution The standard deviation is approximately D years. ' _ (Round the nal answer to two decimal places as needed. Use the expected value and variance rounded to two decimal places. Do not round any other intermediate values.) C. Find the probability that a particular machine 0! this kind will last longer than the mean number of years. The probability is approximately D (Round the final answer to two decimal places as needed. Use the expected value rounded to two decimal places. Do not round any other intermediate values.)