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