Role of Cogito in Descartes’s Meditations

Role of Cogito in Descartes’s Meditations
Explain the role of the Cogito in Descartes’s Meditations and how this leads him to conclude that mind is fundamentally a different substance than the body. What are the differences between mental and material substance? Why does he think mind (rather than body) is the more essential substance in human beings? What are some of the main problems with his approach? (1,200 words)