A hospital director believes that more than 25 % of the test tubes contain errors and feels an audit is required. A sample of 360 tubes found 108 errors. Is there sufficient evidence at the 0.05 level to
substantiate the hospital director's claim?
State the null and alternative hypotheses for the above scenario.

What is the result of adding the system of equations? 2x+y=4 3x-y=6

How many heads would you expect if you flipped a coin twice? first, fill in the table below with the correct probabilities. hint: the sample space for flipping a coin twice is {hh, ht, th, tt}. a = b = c = f

Researchers are conducting experiments to determine the role of alcohol in the development of depression. after the study is complete, they determine that the relative risk of developing depression is 1.55 with a 95 % ci of 1.2 -1.9. each group is then divided into nonsmokers and smokers. the relative risk for the nonsmokers is 1.12 with a 95% ci of 0.87-1.37. the relative risk for the smokers is 1.7 with a 95 % cl of 1.5-1.9. what type of bias may affect this study? a. procedure bias b. recall bias c. selection bias d. confounding e. lead-time bias