i read the section over and over and still cannot find the answer, can somebody help me please?
1. what is the most important long-lasting heat source responsible for geological activity?
a. accretion
b. radioactive decay
c. sunlight
2. which of the following fundamental properties has the greatest effect on its level of volcanic and tectonic activity?
a. mass
b. radius
c. distance from the sun
d. rotation rate
3. some planets in our solar system have relatively few impact craters. this is because:
a the planet was never bombarded by asteroids or comets
b. its atmosphere stopped impactors of all sizes
c. other geological processes have eased most of the craters
4. compare the surface area to volume ration of the moon, mars and earth (surface area is 4pie r sqaure and volume is (4/3) pie r cube. use your answer to discuss differences in the internal heat in these world
5. name 4 important characteristics that can be derived from the time-series velocity measurements
6. name two characteristics of extrasolarplanets that are suprisingly different from planets in our solar system
7. explain the history and fate of water on mars. for example, was there ever surface water on the planet? if so, how long did it last? is it still there today? if not, what happened to it?