Experimental Errors and Uncertainty

Data:
The data table that follows shows data taken in a free-fall experiment.
Measurements were made of the distance of fall (Y) at each of the four precisely measured times. Time, 1 (s) Dist, 9, (n) Dist. y, ((e) Dist. y, (n) Dist, y, (m) Dist. Ye (m)
0 0 0 0 0.5 1.0 1.4 1.1 1.4 1.5 0.75 2.6 3.2 2.8 2.5 3.1 1.0 4.8 4.4 5.1 4.7 4.8 1.25 8.2 7.9 7.5 8.1 7.4
Procedures: From the above data perform the following Tasks.
Task 1. Complete the table. Results 1:
Task 2. Plot a graph versus t (plot t on the abscissa, i.e., x-axis). Results 1:
Task 3. Plot a graph versus t2 (plot t2 on the abscissa, i.e., x-axis). The equation of motion for an object in free fall starting from rest is y = 1/2 gt2, where g is the acceleration due to gravity. This is the equation of a parabola, which has the general form y = ax2. Results 1:
Task 4. Determine the slope of the line and compute an experimental value of g from the slope value. Remember, the slope of this graph represents 1/2 g. Results :
Task 5. Compute the percent error of the experimental value of g determined from the graph in part d. (Accepted value of g = 9.8 m/s2) Results 5: