It looks like your question is incomplete. I believe you also have options to pick which graph is correct. However, I can still give you the information you are looking for.
The slope of the line is -1.2
The Y-intersect is (0, 4)
I have also attached an image of what the graph would look like.
Hope this helps.
D they all have the same slope.
66 more min. he used which could be 1 hour and 6 min.
U/72 = 2/4
means u/72 = 0.5
therefore u = 72*0.5
which equals 36
4.17 x 10^-2 is the answer