As you move through a stationary environment, the location in your visual field at which there is no optic flow (which is also the direction in which you are heading) is called the:

Two trains leave a station at the same time, train a travels at a constant speed of 16 m/s. train b starts at 8.0 m/s but accelerates constantly at 1.0 m/s squared. after 10.0 seconds, which train has the greater speed?