Hank's and Bill's houses are 1 and 3 miles from their school, respectively. Each boy
left his house on a bicycle at the same time
and rode for 30 minutes. The graph above
shows the distance, in miles, each boy was
from the school during their rides. Based
on this information, which of the following
statements, if any, is not necessarily true?
(A) Hank is riding faster than Bill for the
entire 30 minutes.
(B) The distance that Hank rode is greater
than the distance that Bill rode.
(C) Hank and Bill's paths cross exactly once
during their 30-minute rides.
(D) Each of the above statements must be
true.