The document discusses key economic concepts including: 1) Determinants that can shift the demand and supply curves such as changes in income, tastes, prices of related goods, and production costs. 2) The relationship between elasticity of demand and the incidence of an excise tax, with more inelastic demand leading to more of the tax being passed to consumers. 3) How price ceilings and floors can lead to surpluses or shortages depending on where the controlled price is set relative to the market equilibrium.