Im stuck on this problem.

At an altitude of h feet above sea level, the air pressure, P, in inches of mercury (in Hg), is given by P=30e^(-.0000323h)

An unpressurized seaplane takes off at an angle of 30 degrees to the horizontal and a speed of 200 mph.

What is the rate of change of pressure in the plane with respect to time at take-off, in inches of mercury per second?

Converted 200 miles/hours to 3520 inches/second

Converted the vertical rate of change to 3520sin(30)=1760

Derived P to equal 30e^(-.0000323h)(-.0000323)

What should I do next?