Non polar molecule have no partial charge ....so non polar answer !!!
In a chemical change, the atoms in the reactants rearrange themselves and bond together differently to form one or more new products with different characteristics than the reactants. When a new substance is formed, the change is called a chemical change. A chemical reaction is a mechanism that takes place when two or more molecules interact to produce new products. A reaction between two atoms or ions or molecules may take place and a new bond is formed and no atom is destroyed or created, but reactants form a new substance.
True ^_^
I believe B) in both chemical changes and physical changes since in chemical changes, nothing is created or destroyed. In physical changes same thing but with matter.
Step first:
Since, 78.0 percent 
by volume is present in the air which implies there are 78 moles of present in 100 moles of air.
Now,
Mole fraction of = 
Mole fraction =
= 0.78
Partial pressure is equal to the multiplication of total pressure and mole fraction.
Partial pressure = 
(as 1 atm is atmospheric pressure)
= 0.78 atm.
Step second:
Henry's law constant is calculated by:
where,
is solubility of gas
is partial pressure of gas
is henry's law constant
Substitute the value of solubility and partial pressure to find the value of Henry's law constant in above formula:
k = 
= 
Thus, Henry's Law constant is 
.
