A dragster weighing 1600 lbf, attains a speed of 270 mph in the quarter mile. Immediately after passing through the timing lights, the driver opens the drag chute, of area 25 ft^2. Air and rolling resistance of the car may be neglected. Find the time required for the machine to decelerate to 100 mph in standard air. What assumption did you have to make, and was this assumption valid?