Jr friend is at the top of a building which you know to be exactly 100 feet high. a throws a stone downward at a speed '1} ftfsec, and you time how long it takes to the ground. . The distance (in feet) fallen by the stone in t seconds is given by the formula 8 = 167:2 -|- 'U i. (No air resistance.) - You time 2 seconds for the stone to fall to the ground. Using the above formula you can calculate the downward speed which is 18 ft/sec (check it by yourself). However you know your stopwatch is accurate only to within +0.1 sec. 3 a tangent line approximation to infer an error estimate for the downward speed 1r friend threw the stone