How did the Ptolemaic model differ from other proposed solar system models?
It said that the planets have epicycles.
It said that the planets rotate on their axes.
It said that the planets revolve around the Sun.
It said that the planets and the Sun revolve around Earth.

Sorry i dont understand the question can you rephase it?

The atomic nucleus made up from protons (yellow) and neutrons (blue) and held together by nuclear forces. nuclear forces (also known as nuclear interactions or strong forces) are the forces that act between two or more nucleons. they bind protons and neutrons (“nucleons”) into atomic

Ibelieve the answer is weathering,hope my answer has you : ) 

The ratio is 3: 2. i.e. c.