34 multiple-choice questions in College Board exam style. Each has four choices and a full explanation of why each option is right or wrong.
Read the question carefully before looking at the choices. Many APES questions have answers that look almost identical; small wording differences matter.
Know the specific tradeoff of each energy source cold. What's reliable vs. intermittent, what's clean during operation vs. clean overall, and what the specific environmental risk is.
Watch for "baseload" vs. "intermittent" framing. This distinction is tested constantly in Unit 6.
Read the explanations even when you got it right. Each one teaches a small fact that often returns in a different form on the exam.