Hey there!
To start, you have one of your angles given, 40.5. Now, given that the airplane is directly over point A of the triangle, you can conclude that ∠A is 90 degrees.
Knowing that the sum of all the angles of a triangle is 180 degrees, to find ∠P, you can set up this equation (where x is the missing angle of ∠P):
40.5+90+x=180
Simplify and solve for x:
40.5+90+x=180
130.5+x=180
x=49.5
Therefore, m∠P is equal to 49.5 degrees.
Hope this helps and have a marvelous day!