The gravitational force between two object depends on their masses and on their distance.
Since the formula is

If the masses grow, the force also grows. But I'm assuming the two objects are fixed, so you can't enlarge their mass.
So, the only option remaining is to lower their distance: since it sits at the denominator, a smaller value of d results in a bigger value for F.
So, if you reduce the distance between two objects, the gravitational force between them will always result in an increase
Isotopes refer to different atoms of the same element (i.e. same number of protons) that differ in the number of neutrons they have (giving them different atomic weights). Atomic weight is the sum of protons and neutrons (each contributes 1 atomic mass unit).
Carbon has 6 protons by definition. If you have a carbon-13 atom (the 13 referring to its mass), the atom has 13 - 6 = 7 neutrons. Since it's neutral, protons = electrons, so there are also 6 electrons.
Sulfur has 16 protons by definition. If you have a sulfur-32 atom, the atom has 32 - 16 = 16 neutrons. Since it's neutral, protons = electrons, so there are also 16 electrons.
The number of turns of wire is directly proportional to voltage.
The higher the number of turns of wire the higher the voltage
Since .
Power (output) of a generator = voltage x current. Therefore the higher the voltage the higher the output of the generator.
So, the higher the number of turns of wire the higher the output of the generator.