The answer is d. natural gas. All the other choices are alternative sources of energy, and do not produce or emit any greenhouse gas such as carbon dioxide (CO2). Natural gas, on the other hand, is an organic substance containing a significant amount of carbon, that when burned for fuel, results in the emission of CO2.
A gland is an organ that excretes chemical fluids to discharge into the surroundings or for use in the body.
There are three rock types in the rock cycle including: igneous, sedimentary, and metamorphic rock.
<u>Explanation:</u>
Any solid or combination of minerals which naturally occurs is understood as a rock. It is classified by the contained minerals, its chemical composition and the manner it is made.
<u>Igneous Rocks:</u> It is generated by magma or lava being refrigerated and solidified. The magma may be produced from partial melting of established rocks, either in the mantle or crust of a planet. The melting is usually caused by one or more of three methods: temperature rise, pressure decrease, or composition transition.
<u>Sedimentary Rocks:</u> These forms that are developed by aggregation or deposition of tiny particles and eventual cementation of mineral or organic substances on the surface of the Earth's ocean floor or other water bodies. Sedimentation is the general term for mechanisms that cause settlement of such particles.
<u>Metamorphic Rocks:</u> These occur from the alteration of different rock types in a technique called metamorphism, which implies change of shape. The initial rock or protolith is heated where temperatures between 150 to 200 ° C and a pressure level of 100 megapascals (1,000 bar) or more induces significant physical or chemical changes.
Answer:
The temperature at which the reaction changes from non-spontaneous to spontaneous is 588.735 K
Explanation:
The spontaneity of a reaction is determined by the change in Gibbs Free Energy, 
.
If is greater than zero, then a reaction is feasible.
If is less than zero, then a reaction is not feasible.
To determine the temperature at which the reaction changes from non-spontaneous to spontaneous, we should equate the to zero.
We take 
as the limiting condition.
Therefore, the temperature is: 588.735K
