Two machines can run in a plastic bag manufacturing company, the inter-arrivals of raw materials follow a Poisson distribution with a rate of 3 batches per hour. The first machines service time follows a normal distribution with mean of 3 minute and standard deviation of 2 minute, while the second machines service time follows a normal distribution with mean 6 minutes and standard deviation of 1 minute. The long term queue length in the first and second machines would be

21 and 31

None of the above

6.5 and 12

21 and 6.5