At around 20'000ft. and higher.
Answer:
The answer 1 degrees Fahrenheit because you have to subtract 16-15. I subtracted 16-15 instead of putting the negative sign
Square root of 4 is 2
Square root of 9 is 3
7 is between 4 and 9, so its square root is somewhere between 2 and 3, which means the correct answer is between P and Q