When parking a car in a downtown parking lot, drivers pay according to the number of hours

Question:

When parking a car in a downtown parking lot, drivers pay according to the number of hours or parts thereof. The probability distribution of the number of hours cars are parked has been estimated as follows.

Find the mean and standard deviation of the number of hours cars are parked in thelot.

Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...