Q1. Which of the following most accurately describes the relationship between marginal cost (MC), average variable cost (AVC), marginal product (MP), and average product (AP)?

A)   When MP = AP, MC = AVC.

B)   When MP > AP, MC > AVC.

C)   When MP = AP, MC > AVC.

Q2. Which of the following most accurately describes the relationship between the average total cost (ATC) curve and the average variable cost (AVC) curve? The vertical distance between the ATC and AVC curves:

A)   decreases as output increases.

B)   increases as output increases.

C)   increases and then decreases as output increases.

Q3. Which of the following statements regarding marginal costs (MC) and average variable costs (AVC) is most accurate?

A)   MC = AVC when AVC is at its minimum.

B)   MC = AVC when average total cost is at its minimum.

C)   MC = Average total cost when AVC is at its minimum.

Q4. Which of the following most accurately describes the shapes of the average variable cost (AVC) and average total cost (ATC) curves?

A)   The AVC and ATC curves are both U-shaped.

B)   The AVC curve is U-shaped whereas the ATC curve declines initially then flattens.

C)   The AVC and ATC curves both decrease initially, and then flatten.

答案和详解如下：

Q1. Which of the following most accurately describes the relationship between marginal cost (MC), average variable cost (AVC), marginal product (MP), and average product (AP)?

A)   When MP = AP, MC = AVC.

B)   When MP > AP, MC > AVC.

C)   When MP = AP, MC > AVC.

Correct answer is A)

At some output level Q and corresponding labor input L, MC = AVC and MP = AP. At Q and L, AVC is at its minimum and AP is at its maximum. Hint: draw the curves.

Q2. Which of the following most accurately describes the relationship between the average total cost (ATC) curve and the average variable cost (AVC) curve? The vertical distance between the ATC and AVC curves:

A)   decreases as output increases.

B)   increases as output increases.

C)   increases and then decreases as output increases.

Correct answer is A)

The vertical distance between the ATC curve and AVC cost curve is average fixed cost, which decreases as output increases because more output is averaged over the same cost.

Q3. Which of the following statements regarding marginal costs (MC) and average variable costs (AVC) is most accurate?

A)   MC = AVC when AVC is at its minimum.

B)   MC = AVC when average total cost is at its minimum.

C)   MC = Average total cost when AVC is at its minimum.

Correct answer is A)

MC = AVC at minimum average variable cost. MC = ATC at minimum average total cost.

Q4. Which of the following most accurately describes the shapes of the average variable cost (AVC) and average total cost (ATC) curves?

A)   The AVC and ATC curves are both U-shaped.

B)   The AVC curve is U-shaped whereas the ATC curve declines initially then flattens.

C)   The AVC and ATC curves both decrease initially, and then flatten.

Correct answer is A)

The AVC curve is U-shaped, declining at first due to efficiency, but eventually increasing due to diminishing returns. The AFC curve decreases as output increases, and eventually flattens out. The ATC is U-shape because it is the sum of the decreasing-to-flat AFC curve plus the U-shaped AVC curve. ATC = AFC + AVC.