Can y’all give me some awnsers and number to them?

With alll of except for the 2 that i did already

Sara made $253 for 11 hours of work. at the same rate how much would he make for 7 hours of work?

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)