A driver at Dewaan Motors is testing a new model car with a speedometer calibrated to read m/s rather than km/h. The following series of speedometer readings was obtained during a test run along a long, straight road: Time (s) 0 1 3 5 7 9 11 13 15 17 19 Speed (m/s) 0 0 4 7 10 13 17 22 23 26 29 (a) Compute the average acceleration during each 2-s interval. Is the acceleration constant? Is it constant during any part of the test run? (b) Make a (v-t) graph of the data, using scales of 1cm = 1s horizontally and 1cm = 2m/s vertically. Draw a smooth curve through the plotted points. By measuring the slope of your curve, find the instantaneous acceleration at t = 6 s, 18 s, and 25 s.