Can someone please explain how to solve this question?

Which is the product of 58 and 1,000? a. 0.058 b. 5,800 c. 58,000 d. 580,000

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?

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?