A 3 by 4 rectangle is inscribed in circle.What is the circumference of the circle? 

Explanation: To find the circumference of the circle, we need to know its radius. The diagonal of the rectangle is the diameter of the circle, so we can use the Pythagorean theorem to find the length of the diagonal:d^2 = 3^2 + 4^2 d^2 = 9 + 16 d^2 = 25 d = 5Since the diameter of the circle is 5, the radius is half of that, which is 2.5. The circumference of the circle is then given by the formula:C = 2πrSubstituting r = 2.5, we get:C = 2π(2.5) C = 5πTherefore, the circumference of the circle is 5π (or approximately 15.7) units.