1.Fill the blank with "True" or "False" (3 Points)

a.It is impossible to have diminishing marginal return to a single factor (e.g. labor) and constant returns to scale at the same time.

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b.External cost leads to an efficiency loss to society, but external benefit does not.

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c.If all firms in an industry have identical variable cost, but each pays a different one-time fee to enter the market, all firms will produce identical quantities of output

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