Magma may cool and freeze to become solid igneous rock: 
1. when its dissolved volatiles bubble out.
2. faster in the presence of circulating groundwater.
3. within weeks to months, if it intrudes at shallow depth.
4. very slow(centuries to a million years) when it forms a deep pluton.
5. all of the above are true statements.
Factors that influence the chemical composition of magmas may include:
1. the chemical composition of the source rock
2. only partial melting of the source rock.
3. melting and assimilation of some of the rock of the magma chamber walls.
4. mixing of magmas brought together from different locations.
5. all of the above are true statements.
Identify the false statement. The youthful Earth had numerous heat sources for igneous activity, including:
1. conversion of the kinetic energy of colliding planetesimals to heat energy.
2. conversion of the kinetic energy of meteorite impact to heat energy.
3. conversion of the kinetic energy of iron alloys sinking toward Earth's center to heat energy.
4. decay of all of its radioactive elements; almost none remain today.
5. gravity compression of its own mass( compression produces heat).
Identify the false statement. Hot solid rock in the Earth:
1. may experience decompression melting as it rises to shallow depths.
2. may melt if volatiles such as water and carbon dioxide are added.
3. may melt if heat is transferred to it from hot mantle rock rising up into the crust.
4. must reach a minimum temperature of 1100c before it melts.
5. maybe even hotter than surface lava because of the pressure of overlying rock.