Made geocentric model of the solar system using epicycles

Ptolemy made geocentric model of the solar system using epicycles

Explanation:

Ptolemy made geocentric model of the solar system using epicycles.

This model accounted for the apparent motions of the planets in a very direct way, by assuming that each planet moved on a small circle, called an epicycle, which moved on a larger circle, called a deferent.

Therefore, Ptolemy is the answer.

a. spokes of a wheel.

as indicated in the question radial contains rad, also found in radius, so the fracture's would span the radius.