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Suppose the radius of a circle is 16. what issuppose the radius of a circle is 16. what is its circumference its circumference

Lana's family entered a 5-kilometer race lana's average step length is about 0.5 meter how many steps will she need to take the finish

Two cities a and b are 1400km apart and lie on the same n-s line. the latitude of city a is 23 degrees. what is the latitude of city b. the radius of the earth is approximately 6400km.