posted by Kelvin .
For which of the following situations can the equation F = mg not be used to calculate the force due to gravity?
a) The pull of gravity on an apple on the surface of the Earth.
b) The pull of gravity on an airplane flying at an altitude of 8 km above the surface of the Earth.
c) The pull of the Earths gravity on the Moon.
d) The equation can be used for all of the above.