(7-8) - (4 - 5:) = help plz

This is the number of parts out of 100, the numerator of a fraction where the denominator is 100. submit

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

When solving this problem: 3025/5.5 = a/90.75 you get 49912.5 which would be the length of one of the sides of a square when the area is only 90.75 inches. is that answer correct, why, and how is it possible?