Costumers come to a shop according to a Poisson distribution. On average, 3 customers come per minute. a) Find the probability that there will be more than 4 customers in one minute b) A customer has...

Extracted text: Costumers come to a shop according to a Poisson distribution. On average, 3 customers come per minute. a) Find the probability that there will be more than 4 customers in one minute b) A customer has just arrived. Calculate the probability that it will take more than 30 seconds until the next customer arrives.