The area of a circle is found with the formula a = , where represents 3.14. if a tile artist is placing tiles in a circular mosaic pattern and the area of the circle is 658 square feet, what is the approximate radius of the circle in feet?

Anew test for ra is being developed. the test is administered to 750 patients with ra and 750 without ra. for the sake of the question, assume the prevalence of ra in this population is 50%. of the 750 patients with ra, 575 have a positive result. of the 750 patients without ra, 150 have a positive result. what is the positive predictive value of the new test? a575/(575+150) b. 600/(600+ 150) c. 575/(575+125) d. 600/(600+ 125)