If you were doing a research study on sleep and student achievement, which
of the following might be the hypothesis?
O
A. Students get enough sleep to be effective.
O
B. Memory is affected for students.
O
C. Achievement isn't dependent upon sleep.
O
D. The amount of sleep a student gets affects student achievement.

Consider two less-than-desirable options. in the first you are driving 30 mph and crash head-on into an identical car also going 30 mph. in the second option you are driving 30 mph and crash head-on into a stationary brick wall. in neither case does your car bounce off the thing it hits, and the collision time is the same in both cases. which of these two situations would result in the greatest impact force?