reported crimes are believed to occur at random at different rates for different types of crime. the incidence rate for a particular type of crime in city B is 3.0 per week.Show that the probability...

reported crimes are believed to occur at random at different rates for different types of crime. the incidence rate for a particular type of crime in city B is 3.0 per week.Show that the probability of at least 17 crimes of this type occurring in city B in a 4-week period is 0.10
Assuming that numbers of crimes in 4-weekly periods are independent, what is the probability that there will be at least 17 in the last three of the next six 4-week periods? explain your answer