The temperature at which the process be spontaneous is calculated as follows
delta G = delta H -T delta S
let delta G be =0
therefore delta H- T delta s =0
therefore T= delta H/ delta S
convert 31 Kj to J = 31 x1000= 31000 j/mol
T=31000j/mol /93 j/mol.k =333.33K
Light energy into chemical energy
If an atom has 2 protons, then it must also have 2 electrons for there to be no charge. An extra electron will cause for you to have a negative charge, and if you have more protons than electrons, then you will have a positive charge. :)
The second option only.
<h3>Explanation</h3>
A base neutralizes an acid when the two reacts to produce water and a salt.
Sulfuric acid H₂SO₄ is the acid here. There are more than one classes of bases that can neutralize H₂SO₄. Among the options, there are:
Metal hydroxides
Metal hydroxides react with sulfuric acid to produce water and the sulfate salt of the metal.
.
The formula for calcium sulfate 
in option A is spelled incorrectly. Why? The charge on each calcium 
is +2. The charge on each sulfate ion 
is -2. Unlike 
ions, it takes only one ion to balance the charge on each ion. As a result, and ions in calcium sulfate exist on a 1:1 ratio.
.
Ammonia, NH₃
Ammonia NH₃ can also act as a base and neutralize acids. NH₃ exists as NH₄OH in water:
.
The ion 
acts like a metal cation. Similarly to the metal hydroxides, NH₃ (or NH₄OH) neutralizes H₂SO₄ to produce water and a salt:
.
The formula of the salt (NH₄)₂SO₄ in the fourth option spelled the ammonium ion incorrectly.
As part of the salt (NH₄)₂SO₄, the ammonium ion NH₄⁺ is one of the products of this reaction and can't neutralize H₂SO₄ any further.
Answer:
It maintains a constant internal temperature.
Explanation:
Our body tries its hardest to maintain a constant internal temperature. This is because if we get to warm or cold it is unhealthy. If your body senses that it is getting to warm or cold it will try to correct itself.
