why the answer for question 19 is D eventhough it says that

why the answer for question 19 is D eventhough it says that MP is at max when labour changed from 2 to 3 in question 16

Labour per period Total output per period 0 2 3 4 10 30 90 132 150 TABLE 7-3 16) Refer to Table 7-3. The marginal product of labour is at its maximum when the firm changes the amount of labour hired from A) 0 to 1 unit. B) 1 to 2 units. C) 2 to 3 units. D) 3 to 4 units E) 4 to 5 units. Answer: C

Solution

The correct answer should be: C)

Reason: As the MP is maximum at the 3rd unit of labor employed, the required total output must be 90 units.

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