Is 27 a perfect square?
Yes, because there is a number, 54, that equals 27.2.
O No, because the only proper factors of 27 are 3 and 9, and neither of these factors gives 27 when multiplied by itself.
O Yes, 27 = 3-3-3, so 27 is a perfect square because a number can be multiplied by itself to give 27.
O No, because perfect squares must be even numbers.