Please describe the procedure one by one

Let X be the random variable representing the number of parking tickets issued in 1 hour on a weekday for a city. The probability distribution of X is given below. Show work. X 1 2 3 5 p(x] 0.07 0.10 0.20 0.30 a) Find the missing probability in the table above. b) What is the probability that in a particular weekday hour, there will be at least three tickets issued? c) Find the expected number of tickets issued hourly for a weekday. d) Find the standard deviation of number of tickets issued hourly for a weekday