a motorist drives south at 20.0 m/s for 3.00 min, then turns west and travels at 25.0 m/s for 2.00 min, and finally travels northwest at 30.0 m/s for 1.00 min, for this 6.00-min trip, find (a) the total vector displacement. (b) the average speed, and (c) the average velocity. let the positive xaxis point east.