Suppose that Bella is a diligent first-year college student. On Friday, she decides to start the day by working through 300 sample multiple choice problems to study for her computer science class. She starts work at 7:00 AM and uses a table to keep track of her progress throughout the day. She notices that as the hours pass, it takes her more time to solve the problems.

Time	Total Problems Solved
7:00 AM	0
8:00 AM	120
9:00 AM	210
10:00 AM	270
11:00 AM	300

Use the table to answer the following questions.

The marginal, or additional, gain from Bella’s first hour spent working, from 7:00 AM to 8:00 AM, is

problems.The marginal gain from Bella’s third hour spent working, from 9:00 AM to 10:00 AM, is

problems.

The following week, Bella’s computer science faculty advisor gives her some advice. In all their years of teaching, they claim to observe that working on 75 multiple choice questions boosts a student’s test score by about the same amount as spending an hour reviewing lecture notes. For simplicity, assume students are able to review lecture notes at a constant pace during each hour spent studying.

Given this information, in order to use her 4 hours of time spent studying to get the highest possible test score, how many hours should she have spent solving multiple choice problems, and how many hours should she have spent reviewing lecture notes?

1. 0 hours working on problems, 4 hours reading

2. 1 hour working on problems, 3 hours reading

3. 2 hours working on problems, 2 hours reading

4. 4 hours working on problems, 0 hours reading