Answer:
The first graph.
The distance is the vertical axis and time is the horizontal axis.
Distance is a function of time.
Step-by-step explanation:
From the first graph, we see that Elena starts from the first from the school and starts to head towards her home ( this is represented by the line going down). She then goes back to school to her locker (this is shown by the line going up). She must surely spend some time at her school until she gets her stuff ( represented by a horizontal line).
Afterwards, Ellena then starts to head home the second time (represented by the line going down ). However, she meets a friend who invites her to the library to do homework (Her friends' home must be towards her school because the line is then going up). She spends some time at her friends' (shown by a horizontal line). Finally, Ellena heads home and arrives there (represented by the intersection of the line with the x-axis)
Hence, the first graph tells the story of Ellena story.