1) The velocity of a car traveling in a straight line, in feet per second, is shown in the table below. Time, t (sec) Velocity, v ./sec .) On a sheet of graph paper sketch a careful graph of this data and draw a smooth curve through the data. During what intervals of time is the acceleration of the car positive? Find the average acceleration of the car over the interval 0 S t S 50 . Approximate the acceleration of the car at t = 40 seconds. Explain your calculation. What is the greatest distance the car could have traveled during the period from t = O to t = 50 seconds? Comment on any assumptions you are making. (Hint: be careful to overestimate on each interval by choosing either the left or right endpoints, as appropriate.)