The gravitational force of two objects, by definition, is given by:

Where,
G: gravitational constant
m1: mass of object number 1.
m2: mass of object number 2.
d: distance between both objects.
Therefore, according to the given equation, a change that always results in an increase in gravitational force is:
Increase in the mass of the objects and decrease in the distance between them.
Answer:
A change that will always result in an increase in the gravitational force between two objects is:
Increase in the mass of the objects and decrease in the distance between them.
With utmost clarity, that is truest of the truths
Potential energy is defined by formula

here
m = mass
g = acceleration due to gravity
h = height
Now here two different stones are located at same height
while mass of stone A is twice that of stone B
so here we can say potential energy of A is

Similarly potential energy of B is

now if we take the ratio of two energy

so we can say potential energy of stone A is two times the potential energy of B
The formula for this problem that we will be using is:
F * cos α = m * g * μs where:F = 800m = 87g = 9.8
cos α = m*g*μs/F= 87*9.8*0.55/800= 0.59 So solving the alpha, find the arccos above.
α = arccos 0.59 = 54 ° is the largest value of alpha
Acceleration = (change in speed) / (time for the change)
= (49 m/s) / (5 seconds)
= (49 / 5) m/s / s
= 9.8 m/s²