To pass safely you must be able to see clearly how much of a mile of the road ahead

we can solve this via the kinematic equation:

where the vertical velocity is zero and so:

since the height of the building is 29.3 meters then:

the ball was in motion for approximately 2.45 seconds

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.