Given: Air pressure may be represented as a function of height above the surface of the Earth as

Where h is the height in meters and

Required: To find out which equation will find the height at which air pressure is 65% of the air pressure at sea level.
Explanation: We are given that air pressure is 65% of the air pressure at sea level i.e.

Now putting this value of P in the given function we get

This is equivalent to the expression given in option A.
Final Answer: Option A is correct.