Charlie, Alexander, and Nate went to lunch. The bill, before sales tax and tip, was $37.50. A sales tax of 8% was added. A) How much was the sales tax?

B)How much was the total bill including tax?

C) The group then tipped 18% on the amount after the sales tax was added. How much did they leave as a tip?

D)What was the total cost of lunch including tax and tip?

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)