The answer is

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Before we rationalize the denominator, we must simplify the numerator and denominator. We evaluate the square root on the top, and combine like terms on the bottom:

To rationalize the denominator, we multiply by the conjugate. The conjugate is found by making the imaginary term of the complex number, the i part, the opposite sign. The conjugate of -2-i is -2+i:
Attached is a picture of my answers.
(2, 0) (2, 7) assuming that Y can equal anything.
There are 75 girls because you add the ratio 3+5 = 8 then divide 120 by 8 to get 15 then there are 5 lots of girls so multiply 15 x 5 to get 75
hope this helps !