Vector u has its initial point at (21, 12) and its terminal point at (19, -8). Vector v has a direction opposite that of u, whose magnitude is five times the magnitude of v. Which is the correct form of vector v expressed as a linear combination of the unit vectors i and j? A. v = -10i + 4j B. v = -0.4i − 4j C. v = 0.4i + 4j D. v = 15i + 100j