queuing theory:

A laboratory contains a microcomputer. The users arrive according to a Poisson process of parameter x=3 users per hour. The duration of use of a microcomputer is an exponential random variable of mean 10 minutes per user. All the operating characteristics are verified 1. Compute the average waiting time in the queue 2. Calculate the average number of users in an 8-hour day and the corresponding average service time. 3. Calculate the number of hours of inactivity of this device per 8-hour day 4. Calculate the amount of time lost each day by the users due to waiting.

Please provide calculation