Final answer:
Elena's opportunity cost of delivering one pizza is 2/3 of a pizza she could have made, as she can make 10 pizzas per hour and deliver 15 pizzas per hour.
Step-by-step explanation:
The student's question asks about the opportunity cost for Elena when she delivers a pizza. Given that Elena can make 10 pizzas per hour or deliver 15 pizzas per hour, we can calculate her opportunity cost of delivering a pizza by comparing the two rates of production for making and delivering pizzas.
To find the opportunity cost, we need to know how many pizzas Elena could have made in the time it takes her to deliver one pizza. If Elena can deliver 15 pizzas in an hour, then each delivery takes her 1/15 of an hour. Now we calculate how many pizzas she could have made in that time: 10 pizzas (made per hour) × 1/15 hour (per delivery) = 2/3 of a pizza. Therefore, the opportunity cost of Elena delivering one pizza is 2/3 of a pizza she could have made.