A student has been asked to determine the linear acceleration of a toy car as it moves down a slope. He sets up the apparatus as shown in the first figure below
The time 
to move from rest through a distance 
is found for different values of . A graph of (y-axis) is plotted against 
(x-axis) as shown in the second figure below
Determine the gradient of the line of the graph in the second figure.
Use your answer to (a) to calculate the acceleration of the toy down the slope. Explain your working.
.
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