Draw a supply and demand graph and place the lower price at 0. Draw an isoquant line from this point to the lower right corner of your graph. This isoquant line represents the quantity demanded at that price. Denote this quantity by Q1. Now draw an isoquant line from Q1 to the upper left corner of your graph. This isoquant line represents the quantity supplied at that price. Denote this quantity by S1. The slope of the lines tells you how much more (or less) a unit of Q1 will be purchased than a unit of S1. So, if the slope of the lines is positive, then there is higher demand for Q1 relative to S1 and you would find quota rent at that price. If the slope of the lines is negative, then there is lower demand for Q1 relative to S1 and you would find quota rent at that price. In most markets, there will be some amount of quota rent