Which of the following are trade$-$offs faced by a professor deciding how much time to spend preparing for class? Check all that apply.

The professor has taught the same subject for $4$ years.

The professor likes the students a lot.

The better the lecture, the better the professor's chances of tenure, but time spent preparing the lecture decreases the time the professor has available to work on research.

Which of the following are trade$-$offs faced by a recent college graduate deciding whether to go to graduate school? Check all that apply.

If she goes to graduate school, she won't be able to start a new job and repay her existing student loans.

She is currently studying biology.

She graduated college with distinction.

Which of the following are trade$-$offs faced by a single parent with small children deciding whether to take a job. Check all that apply.

Childcare is expensive for working parents, but it promotes social skills in small children.

Working prevents parents from attending their children's sporting events.

They can make more money by working, but they won't be able to home$-$school their children anymore.