Everything and what does y equal? ?

Evaluate 4 a for a = 5 2/3 . express your answer in simplest form.

How do you use the additive inverse to evaluate an expression that uses subtraction in a full sentence

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?