12. Which is a disadvantage of using solar or wind energy to produce electricity?
A. They are controlled energy resources
B. These energy sources are nonrenewable
C. They are an expensive way to produce energy
D. Their ability to produce energy is inconsistent and variable

What is the temperature of one mole of helium gas at stp?

Plz mark brainliest 30 points 1) find the momentum of a 12 kg snowball that is rolling with a velocity of 9 m/s. 2) an 8 ball with a mass of .5 kg is sitting at rest. it is hit by the cue ball (1 kg) traveling at 2.5 m/s. if the cue ball is at rest after the collision, how fast is the 8 ball traveling after the collision? 3) two football players are running toward each other. if the offensive player is 75 kg and is running 8 m/s, how fast must the 60 kg defensive player run in order for the two players to hit and stop?

Compare and contrast refraction of light and sound will give brainliest