Which of the following is a way for energy to pass from one trophic level to the next?
a. production of waste
b. decomposition
c. feeding
d. all of these

How many molecules are present in 3 mols of silicon dioxide (sio2)?

An object moves from the position +34m to the position -15m in 15 seconds. what is it's total displacement? what is it's average velocity?

If an astronaut takes an object to the moon the following is true (choose only one). a the mass will change but the weight will be the same. b both the mass and the weight of the object will be the same. c the weight will change but the mass will be the same. d both the mass and the weight of the object will change.