What is 21/3= to in radical form

The hawaiian alphabet has 12 letters. how many permutations are posible for each number of letters?

Factor the monomial completely 42a3b3

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?