A company that makes an exercise machine asked some of its recent customers how long they have owned their machines and how many hours per month they currently use their machines. Which of the following is the best estimate of the average change in hours of exercise per month that was associated with a 1 month increase in ownership?
A.
-5 hours
B.
-3 hours
C.
-3/4 hours
D.
-1/3 hours

On a certain portion of an experiment, a statistical test result yielded a p-value of 0.21. what can you conclude? 2(0.21) = 0.42 < 0.5; the test is not statistically significant. if the null hypothesis is true, one could expect to get a test statistic at least as extreme as that observed 21% of the time, so the test is not statistically significant. 0.21 > 0.05; the test is statistically significant. if the null hypothesis is true, one could expect to get a test statistic at least as extreme as that observed 79% of the time, so the test is not statistically significant. p = 1 - 0.21 = 0.79 > 0.05; the test is statistically significant.