Rina's Performance Pizza is a small restaurant in Denver that sells gluten-free pizzas. Rina's very tiny kitchen has barely enough room for the four ovens in which her workers bake the pizzas. Rina signed a lease obligating her to pay the rent for the four ovens for the next year. Because of this, and because Rina's kitchen cannot fit more than four ovens, Rina cannot change the number of ovens she uses in her production of pizzas in the short run.
FILL IN THE BLANKS:
However, Rina's decision regarding how many workers to use can vary from week to week because her workers tend to be students. Each Monday, Rina lets them know how many workers she needs for each day of the week. In the short run, these workers are (variable or fixed) inputs, and the ovens are (fixed or variable) inputs.

Rina's daily production schedule is presented in the following table.
Fill in the blanks to complete the Marginal Product of Labor column for each worker.

Number of Workers Output Marginal Product of Labor
(Pizzas) (Pizzas)
0 0
1 60
2 100
3 130
4 150
5 160