(1) For what check value can Mr. Zngg spend the least money and end up with exactly N times the original amount?

(2) For what check value must Mr. Zngg spend the most money in order to end up with exactly N times the original amount?

(3) For what check value can Mr. Zngg spend an amount of money closest to his original check and end up with exactly N times the right amount? [The amount of the check will determine the value of N, which must be a positive integer. D and C are both 2-digit numbers.]