force can be thought of as either a push or a pull, as long as it makes the object move in a circular path.

Centripetal

Explanation: The centripetal force refers to the acting on a body moving in a circular path. This force acts in the direction of the center of rotation. The centripetal force is given by :

F = mv^2 / r

Where m = mass of th body

v. = Velocity

r = radius of the circular path.

For an object to move in a circular path, the force required is called the centripetal force. It is measured in Kgms^-2. It is directly proportional to the product of the Mass and square of it Velocity and varies inversely to the Radius of its path.

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.