Aplane traveling from phoenix to san francisco with a tailwind of 35 miles per hour takes 2.5 hours. returning with the headwind it takes the same plane 2 hours and 45 minutes. what is the average speed of the plane in calm conditions?

The price of a car has been reduced from $19,000 to $11,590. what is the percentage decrease of the price of the car?

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)

The function h (t) = -16t squared + 28t + 500 represents the height of a rock t seconds after it's propelled by a slingshot what does h (3.2) represent?