Consider the points P(r.s,t), where r, s, and t are real numbers, and Q(5,3,-7). Complete parts (a) through (c). a. Find PQ and state your answer in two forms: (a, b, c) and ai + bj+ck. PQ-00-0i+Oj+Ok b. Find the magnitude of PQ. The magnitude of PQ is c. Find two unit vectors parallel to PQ OA. O B. H 5 (3-3)+(-7-1) OC. OD. 3 -7 (5-1)+(-7-1 (5-1)+(3-3) 5-r 3-s -7-1 (5-1)+(3-5)+(-7-1) (5-1)+(3-3)+(-7-1) (5-1)+(3-5)+(-7-1 (3-3)+(-7-1 (5-1)+(-7-1 (5-1)+(3-5) * (5-1) + (3-35) (5-1) (3-s) (-7-1) (5-1) + (3-5) + (-7-1) (5-1)+(3-3)+(-7-1)2 (5-1)+(3-3)+(-7-1