Rewrite the definition “all right angles measure 90 degrees” as a biconditional statement using “if and only if”.

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

At the beginning of year 1, carlos invests $600 at an annual compound interest rate of 4%. he makes no deposits to or withdrawals from the account. which explicit formula can be used to find the account's balance at the beginning of year 5? what is, the balance?

Factor the polynomial, if possible. if the polynomial cannot be factored, write prime. 9n^3 + 27n^2 – 25n – 75