1. What are the two sources of thermal energy in Earth's interior?
A. solar heating and gravity
B. combustion and solar heating
C. gravity and radioactive decay
D. radioactive decay and combustion

Which piece of equipment would me most useful for measuring the volume of some water? a. pan balance b. graduated cylinder c. tweezers d. flask quick

How many moles of carbon dioxide will form if 2.5 moles of c3h8 is burned

If we compare and contrast electromagnetic waves with sound waves, all but one statement is true. that is a) sound waves require a medium to travel while electromagnetic waves do not. b) electromagnetic waves can travel through the vacuum of space while sound waves cannot. c) electromagnetic waves must have a medium in which to travel, but sound waves can travel anywhere. eliminate d) sound waves must bounce off of matter in order to travel while electromagnetic waves do not require matter to be present.