A student solved for the radius of a circle with a circumference of 12π. In which step did the student make an error?

This is so harddd! solve. 1 + 1 = solve 4 + 4 = solve 3 x 3

Aplane flies around trip to philadelphia it flies to philadelphia at 220 miles per hour and back home with a tailwind at 280 miles per hour if the total trip takes 6.5 hours how many miles does the plane fly round trip

Joanie wrote a letter that was 1 1/4 pages long. katie wrote a letter that was 3/4 page shorter then joagies letter. how long was katies letter