The average velocity of a car is determined by computing v = dit, where t is the time to travel distance d. The distance is known to be exactly d = 50 ft. The time + is measured with a stopwatch. Accounting for measurement uncertainty, the time is 1.2 ‡ 0.1 s at 95% probability. What is the uncertainty in vat 95% probability? (a) 6.94 ft/s (b) 3.21 ft/s (C) 3.79 ft/s (d) 3.50 ft/a (e) 7.00 (f) none of the above