A car and a truck are moving at different constant speeds in the same direction on a highway. The following graph shows their positions as a function of time.
At what time are the two vehicles less than 1 mile apart?
O Between 12:06 p.m. and 12:12 p.m.
O Between 12:06 p.m. and 12:18 p.m.
O Before 12:06 p.m. and after 12:12 p.m.
O Before 12:06 p.m. and after 12:18 p.m.