The cost of opportunity is by definition the amount of things you don't do or buy, because of choosing doing or buying something else. In this case, Maria can make:
8 pancakes
2 waffles
This means that at every moment, she can choose to make or 8 pancakes or 2 waffles, but not both. If we continue with this logic, in the time she could make 1 waffle, she could have chosen to make 4 pancakes. This is her cost of opportunity.
The answer and procedures of the exercise are attached in the following archives.
Explanation
You will find the procedures, formulas or necessary explanations in the archive attached below. If you have any question ask and I will aclare your doubts kindly.
