Assess undergraduate students' understanding of basic supply and demand principles and market equilibrium in competitive markets. Scope: define supply and demand and key determinants, interpret and sketch supply and demand curves, distinguish movements along versus shifts of curves, identify equilibrium price and quantity and explain effects of shifts (surplus/shortage), and evaluate basic impacts of simple price controls (ceilings and floors). Emphasize conceptual and graphical reasoning; quantitative work limited to reading and comparing values.