Gravity plays the central role; without gravity, there would be no such thing as an orbit.
Gravity keeps things together here on Earth. It keeps the Earth together in the first place, and it keeps us on Earth. It keeps the Earth in orbit around the Sun, and it keeps the Moon in orbit around Earth.
Both what?
uidsfdhjv"vbnhdf jkdf
It keeps the solar system together because without it we would be floating around. :)
Mutual gravitational attraction between the Earth and moon keep the moon in orbit. Conservation of angular momentum may also be considered to play a role.
I am not sure that it makes sense to say that anything holds the Earth. The Earth is a planet in space, which orbits the sun. Gravity holds it in orbit, and gravity holds it together. The incompressible matter of which it is composed, holds up the surface, for our convenience as its inhabitants. Every layer, the inner core, the outer core, the mantle, and the crust, has a role to play in making our planet what it is.
Describe how gravity inertia and friction play a role in throwing a ball
It doesn't!
gravity pulls it.
specific examples on the role of the oceans play on the earth
Gravity is the force that keeps galaxies and solar systems together.
It makes it spherical.