Why is the earth's surface warmer than the surface of other planets, like mars?
a. the earth's atmosphere releases heat.
b. the earth's surface receives less energy from the sun's rays.
c. the earth's rotation transfers energy more evenly.
d. the earth's atmosphere traps heat.

Identical marbles are released from the same height on each of the following four frictionless ramps . compare the speed of the marbles at the end of each ramp. explain your reasoning

Global warming will produce rising sea levels partly due to melting ice caps but also due to the expansion of water as average ocean temperatures rise. to get some idea of the size of this effect, calculate the change in length of a column of water 1.00 km high for a temperature increase of 1.00ºc. note that this calculation is only approximate because ocean warming is not uniform with depth. (answer in ×10^{-3} −3 m)

The particles that are found in the nucleus of an atom are