Answer:
a) third; from left most graph
b) fourth; right most graph
Explanation:
Part a)
The graph is between the speed and time.
Nicole begin jogging faster and faster i.e. speed is increasing w.r.t time thus we have linear line in beginning.
Then she hits a comfortable speed and stayed at it i.e. speed remained constant for that time. Thus we have a straight line.
After that she gradually slows down,i.e speed is decreasing w.r.t time. Thus we have decreasing linear line.
So the graph shape is linear line with increasing slope-a constant straight line-linear line with decreasing slope
which is the third; from left most graph in option
Part b)
The graph is between Distance to campus and time.
As Dale is hiking towards campus, distance should decrease w.r.t time.
In beginning, he is hiking at constant speed towards campus thus the distance towards the campus is decreasing w.r.t time. We get a decreasing linear line.
*Note: here constant speed is not important, instead hiking towards i.e. the direction is important because of the campus distance covered
Then he sees a snake and turn and runs the other way. Thus now the distance towards the campus is increasing. And we get increasing linear line.
*Note running other way is important because of the campus distance covered
After that, he sits for a while i.e he stops and so the distance towards campus also become constant w.r.t time. we get a straight line on the graph.
So the graph shape is linear line with decreasing slope-linear line with increasing slope-a constant straight line
which is the right-most graph in option !