Supply Practice! In each of questions I-14, an event has occurred that will affect the supply or quantity supplied of a good. Illustrate the change in supply or quantity supplied for the good that is listed below the graph. To illustrate a change in supply (also called a shift of the supply curve), draw a parallel line to the right or left of the original line, plus an arrow to indicate the direction of the shift. To illustrate a change in the quantity supplied (also called a movement along the supply curve), indicate two points on the supply curve, and draw an arrow pointing up or down the curve between the two points. cides to subsidize oil