The demand curve for labor of a competitive firm,MRPL in (a), takes the product price as given.But as the wage rate falls from $15 to $10 per hour,the product price also falls.Thus the firm's demand curve shifts downward to MRPL2. As a result,the industry curve,shown in (b),is more inelastic than the demand curve that would be obtained if the product price were assumed to be unchanged. The demand curve for labor of a competitive firm, MRPL1 in (a), takes the product price as given. But as the wage rate falls from $15 to $10 per hour, the product price also falls. Thus the firm's demand curve shifts downward to MRPL2. As a result, the industry curve, shown in (b), is more inelastic than the demand curve that would be obtained if the product price were assumed to be unchanged