A motorist drives south at 20.0 m/s for 3.00 min, then turns west and travels at 25.0 m/s for 2.40 min, and finally travels northwest at 30.0 m/s for 1.00 min. For this 6.40 min trip, find the following values.
(a) total vector displacement m (magnitude) south of west
(b) average speed
(c) average velocity (magnitude) south of west