In the mathematical equation showing that volume (V) divided by temperature (T) remains equal to a constant (k), volume and temperature are proportional

Directly  

Explanation:

If V increases, then T must also increase to keep the same ratio.

If V decreases, then T must also decrease to keep the same ratio.

V and T are directly proportional, because a change in one always causes a change in the other and the changes are in the same ratio. The constant k is called the proportionality constant.

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be