pls answer quickly

a) i) A car park has a capacity for 5 cars. The arrival of cars is Poisson at a mean rate of 10 per hour. The length of time each car spends in the car park has negative exponential distribution with mean of 2 minutes. How many cars are in the car park on an average and what is the probability of the newly arriving customer nding the car park full and leaving to park his car elsewhere. ii) In a production shop of a company. the breakdown of the machines is found to be Poisson with the average rate of 3 machines per hour. Breakdown time at one machine costs Rs. 40 per hour to the company. There are two choices before the company for hiring the repairman. One of the repairman is slow but cheap, the other fast but expensive. The slow repairman demands Rs. 20 per hour and will repair the broken down machines exponentially at the rate of 4 per hour. The fast repairman demands Rs. 30 per hour and will repair the machines exponentially at an average rate of 6 per hour. Which repairman should the company hire