In a coffee vending machine, coffee is dispensed into a disposable cup before coffee creamer is added. The amount of time it takes to dispense coffee from the machine is represented by a mean time of 45 seconds and a standard deviation of 3.5 seconds. This is followed by the addition of coffee creamer, which has a mean time of 10 seconds and a standard deviation of 2 seconds. The addition of creamer follows immediately after the dispensing of coffee.

a. (2 pts)What is the mean time required for the entire process?

b. (3 pts)The times for the two processes to take place - dispensing coffee followed by coffee creamer - are independent. Find the standard deviation of the time required to complete the entire process.