What three variable factors determine the force of gravity between any two objects

The force of gravity between two objects is:
F = G*m1*m2/r^2

So, it is dependent of the two masses and the distance between their centers of mass.

If, you are referring to the force of gravity due to the earth, then the two factors are the mass of the object and the distance from the center of mass of the object and center of mass of the earth.

Mass of the first object Mass of the second object Distance between the two objects

    5.5 n======    assuming that      we have      m = 0.145 kg    a = 38 m/s²therefore    5.51 n, but two significant figures.final answer: 5.5 n