If a firm hires additional workers, ceteris paribus the marginal physical product of labour usually will

a.increase, because larger firms are more efficient.

b.decrease, because new workers are likely to be less able than the previously hired ones

c.increase, because more workers can always get more work done.

d.decrease, because each worker now has less capital and other resources to work with.

The marginal physical product of labour declines as the number of workers increases because

a.of diseconomies of scale.

b.of the law of diminishing marginal returns

c.firms must lower prices for the final product when they want to sell more units.

d.firms hire the most efficient workers first and the least efficient workers last

As the wage rate rises, other things constant, firms will choose to employ

a.more workers.

b.fewer workers.

c.the same number of workers.

d.less capital.