CPUD owns 1 supercomputer that can be accessed through the internet. Their customers send jobs that arrive on average every 3 hours. The standard...

CPUD owns 1 supercomputer that can be accessed through the internet. Their customers send jobs that arrive on average every 3 hours. The standard deviation of the inter arrival times is 7 hours. Executing each job takes on average 2 hours on the supercomputer and the standard deviation of the processing time is 5 hours. How long does a customer have to wait to have a job completed?