please ignore the monkey, it's related to another question

1. If & = (m, n, 1) is perpendicular to both a = (5, 1, -2) and b = (3, -3,6), find m and n. [TH -5] 2. ABCD is a quadrilateral where W, X, Y, and Z are respectively the midpoints of AB, BC, CD, and AD respectively. Prove that WXYZ is a parallelogram. [TH - 5] 1. Suppose that OP = (a. -6,c) and oQ = (3,b,-9), where OF = 00 What are the corresponding values of a, b, and c? b= c=. b. Why are we able to be certain that the determin ed values are correct? 2. Given two vectors, a = (a,,d;,a, ) and b = (b,.by.b, ), describe how you would determine whether they are perpend 3. Determine the unit vector of a = (9,-12, 15) 4. Given a = (1,3,-3), 5 = (-3,6,12),