In parallelogram ABCD, the measure of angle A is 99°. What are the measures of the other 3 angles? Explain how you know.

Use mathematical induction to prove the statement is true for all positive integers n, or show why it is false. 1^2 + 4^2 + 7^2 + + (3n - 2)^2 = [n(6n^2-3n-1)/2]