Carskadon study on starting times for schools concluded that early school starting times

Early school starting times cause poor performance on tests, inattention in class, and drowsiness.

Explanation:

Carskadon study on early school starting time showed that it cause increased rate of rapid eye movement sleep in students and they doze off during lecture. Insufficient sleep lessens attentiveness levels in the class which affects students' potential to learn. The study showed that students do not perform well on tests. In addition to the difficulty in learning, there is an increased danger of accidents for those who drive to school due to dizziness.

hey there! :

mass = 5.75 g

volume = 7.5 cm³

therefore:

density = mass / volume

d = 5.75 / 7.5

d = 0.7 g/cm³

answer c

hope that !

only #2 represents an object at rest on a table.

in #1, there is no normal force due to the table; the object is accelerating downward.

in #3, the vertical forces are not balanced; the object is accelerating downward.

in #4, neither the vertical nor the horizontal forces are balanced. the object is accelerating upwards and to the right.