Answer:
Lisa travels faster than Bill. Option (a) is true.
Explanation:
From the given equation, we can see that Lisa's speed is 7 m/s, which is constant.
Bill's speed, on the other hand, varies throughout his journey.
We can estimate his average speed by calculating the slope of the line on the graph.
Here's the calculation:
speed_bill = (d_bill[-1] - d_bill[0]) / (t_bill[-1] - t_bill[0])
= (20 m - 2 m) / (10 s - 1 s)
= 18 m / 9 s
= 2 m/s
Since 7 m/s > 2 m/s, we can conclude that Lisa travels faster than Bill.
Thus, Option (a) is true.