kachina is a senior majoring in graphic design at awesome university (au). while she has been attending college, kachina started a computer consulting business to help senior citizens learn how to use their ipads. kachina charges $25 per hour for her consulting services. she also works 5 hours a week for the economics department to maintain that department's web page. the economics department pays kachina $20 per hour. Refer to Scenario 13-2. If Kachina can work additional hours at either job, what is the opportunity cost if she spends one hour reading a novel? a. $20 b. $125 c. $25 d. $100