B shows a line going up, then straight, then up again. This shows that he was riding away from home, stopped, then rode further away, which is why the line looks the way it does.
U should know the area of rectangle is w*l if we increase it by double or times 2 its area will be A=2w*2wl A=4wl area would be 4 times of original one Now u can get the answer
