If you are testing how the amount of sleep students get affects test performance, what should you change in the experiment? a. the grading of the test b. which teacher each student has c. how much sleep each student gets d. how many questions are on the test

Luke and carrie are driving down a straight section of the interstate at 70 mph in luke's new convertible. carrie is drinking a soda in the passenger seat. when she is done she tosses the bottle straight up in the air, just above the height of the car. what will happen to the bottle if air resistance is neglected? a. the bottle will land in carrie's lap. b. not enough information is given. c. the bottle will land on the interstate in front of the car. d. the bottle will land on the interstate behind the car.

Astone is dropped from a cliff and falls 9.44 meters. what is the speed of the stone when it reaches the ground? a. 13.6 m/sec b. 1.39 m/sec c. 185 m/sec d. 9.80 m/sec

How do you know how many valence electrons an atom has?