A store opens at 8 in the morning. from 8 until 10 customers arrive at poisson rate 6 per hour. Between 10 and 12 they arrive at a poisson rate of 10 per hour. From 12 to 2, the store closes for lunch, Finally from 2 to 5 the arrival rate drops linearly from 10 per hour at 2 to four per hour at 5. Determin the mean number of customers that enter the store on a given day.

Firstly Im not sure what to do here except maybe from 2 to 5 we can say the Mean rate is 7 per hour?

Thanks in advance!