a family took 2 hours to drive from city a to city b at a speed of 55 miles per hour. On the return trip, due to a snowstorm, the family took 3 hours to travel back to City a. How many miles did the family travel in all? What was teh average speed for the entire trip?

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)