If you are currently using a gas or electric pool heater, the savings from solar pool heating system will pay for itself in 2-3 years of installation. For example, the average system costs about $5,500 and it typically costs about $2,000 a year to heat a pool with gas.
In the United States, enrollment in AP Statistics classes has increased at a higher rate than in any other AP class. Students may receive college credit or upper-level college course placement upon the successful completion of a three-hour exam ordinarily administered in May.
View AP Exam calendar. The exam is 3 hours long and has two sections â multiple choice and free-response. Section I: Multiple Choice | 40 Questions | 1 hour and 30 minutes | 50% of Exam Score. Section II: Free-Response | 6 Questions | 1 hour and 30 minutes | 50% of Exam Score.