The number of train passengers who fail to pay for their tickets in a certain region has a poison distribution with a mean of 4 per train

i) all passengers pay their ticket?

ii) More than 1 passenger fail to pay for their tickets

If there are 4800 trains per month in the region,

iii) Find the expected number of trains with at least 1 non paying passenger.

iv) Calculate the average cost to the train company during a month if the average cost of a ticket is $12.54