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Suppose the product market is perfectly competitive with price $1 . All firms have marginal product of labour given by MPL = 32-2L and the market wage is $12. A firm's marginal revenue product of labour curve has vertical intercept :I and slope |:| . At the market wage, the firm will employ |:| workers. If the union raises the wage by $1 above the market wage. it can expect the firm to reduce employment by