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In a market economy, O demand is determined by supply. O supply is determined by demand. O price is determined by quantity. quantity is determined by price. ) Either a or b are correct, depending on the product. QUESTION 3 Figure 4-7 Price 35 30 25 20 15 10 5 100 200 300 400 500 600 700 800 Quantity Refer to Figure 4-7. At a price of $35 O there would be a shortage of 400 units. O there would be a surplus of 200 units. O there would be a surplus of 400 units. O the market would be in equilibrium