Kylie explained that (–4x + 9)2 will result in a difference of squares because (–4x + 9)2 = (–4x)2 + (9)2 = 16x2 + 81. which statement best describes kylie’s explanation?

a=kylie is correct.
b=kylie correctly understood that it is a difference of squares, but she did not determine the product correctly.
c=kylie did not understand that this is a perfect square trinomial, and she did not determine the product correctly.
d=kylie determined the product correctly, but she did not understand that this is a perfect square trinomial.

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?