2022, Set 2, Question 3 · Short · 5 points
Regulating a natural monopoly with a subsidy
Read a natural monopoly graph to identify the returns to scale and the zero-profit price and output. Under a price ceiling at the socially optimal output, compute revenue, explain why a subsidy is needed, and compute the lump-sum subsidy.
This exam had three free-response questions in a 60 minute section (10 minutes of reading and 50 of writing), with about half the time suggested for Question 1 and the rest split evenly between Questions 2 and 3, and the scoring guidelines label Question 1 long and Questions 2 and 3 short. The current exam has 3 free-response questions in 60 minutes. The skills these questions practice still count.
Lessons this question draws on
1 Read the question
The question is College Board's, from the 2022, Set 2 exam. It starts on page 5 of the PDF. College Board no longer posts this exam, so it opens from the copy of College Board's PDF that the Internet Archive saved on December 20, 2025.
2 Write your answer
Answer each part the way you would on the exam, in full sentences, with your work shown. Your writing saves as you type.
3 Score it
Score your answer against College Board's scoring guidelines, one point at a time. Give yourself a point only when your answer says what the guideline asks for.
Scoring guidelines (PDF, page 6) What the exam readers saw (Chief Reader report)
Question, scoring guidelines and Chief Reader report: College Board, from the Internet Archive. The title, summary are ours.