Will mark brainliest if you answer a few easy questions! asap! !

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $32.09. find the probability that a randomly selected bill will have an amount greater than $155, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?

Abacteria population is tripling every hour. by what factor does the population change in 1/2 hour? select all that apply

Can someone me out here number 4 plz