Finally, you got one wrong. The correct answer is 9.42 inches. To find the circumference of a circle you multiply the diameter by 3.14 (pi).
The good news is you can skip Volumes 1 - 3 and start with Volume 4 of the Learn Math Fast System. It will only take you about a month to complete that short book. You did really well on this test. Use the coupon code PT2026 to get 10% off your order.