Which of the following is a tool used for protectionism?

For spring break, Melanie will either stay home or go to Daytona Beach. At home, Melanie pays $10 per day for food and earns $90 a day at her job. At Daytona Beach, Melanie will stay with friends and so has no lodging cost

She will pay $20 per day for food. In terms of dollars, Melanie's opportunity cost per day of going to Daytona Beach is how much?

In Porter's Five Competitive Forces model, "competition from substitute goods or services" refers to

A) substitute products that come from outside the industry. B) substitute products that come from foreign competitors in the same industry. C) substitute products that come from domestic competitors in the same industry. D) competition from producers of substitutes who outsource their production.