Which of the following best describes the solar radiation absorbed by and radiated from earth?
a. most incoming solar energy is absorbed by the atmosphere.
b. only a small fraction of energy radiating from earth is from the atmosphere.
c. the earth’s surface is responsible for a small fraction of heat radiation to space.
d. earth’s surface absorbs little of the energy that strikes as solar radiation.

c. The Earth’s surface is responsible for a small fraction of heat radiation to space.

Explanation:

In later ages the large amount of sun's energy is reflected back by the terrestrial surface back to the space. But now due to the abundance of large concentration of greenhouse gases in the atmosphere is responsible for the absorption of thermal energy from sunlight by these gases causing the atmosphere to be hot. This is the reason of global warming. Now only small fraction of heat is radiated back to the space.        

d

explanation:

the atomic number of magnesium is 12. its nucleus must contain 12 protons and no electrons. the atomic number of an atom is determined by the number of protons.

magnesium is an electrolyte injection commonly used to treat low magnesium levels in your blood. it is also used to prevent or control seizures in women with preeclampsia or eclampsia.