In Exercises 39-42, let R = (-2, 7). Calculate the following: 39. The length of OR 40. The components of u = PR, where P = (1, 2) 41. The point P such that P R has components (-2, 7)Figure 20(A) 56. What are the coordinates a and b in the parallelogram in Figure 26(B)? (-1, b) OW- (2, 3) (-3, 2) (a, 1) which (B) FIGURE 26 -36) 57. Let v = AB and w = AC, where A, B, C are three distinct points in rmine the plane. Match (a)-(d) with (i)-(iv). Hint: Draw a picture. (a) -w (b) -v (c) w - V (d) v - w (i) CB (ii) CA (iii) BC (iv) BA