1. Compute the dot product (a) (1 Point) (3, -1, 8) . (3, 5, 5) (b) (1 Point) (8i + 4j - 2k) . (-i+ j + 3k) 2. (1 Point) Find the angle between the vectors a = (1, 1, 1) and b = (1, -2, 2). Give your answer as an exact value involving an arccosinc. 0 = 3. (1 Point) Find all values of a for which the angle between the vectors (2, 1, -1) and (1, a, 0) is # /4 radians. a =