1. The typical total-cost curve is U-shaped. 

 3. The shape of the total cost curve is related to the shape of the production function. 

4. If the marginal cost of producing the tenth unit of output is $3, and if the average total cost of producing the tenth unit of 

output is $2, then at ten units of output, average total cost is rising. 

5.       The marginal cost curve intersects the average total cost curve at the minimum point of the average total cost curve. 

2. If a firm produces nothing, it still incurs its fixed costs.