A answer choices- Experimental Study Observations study Answers choices for B -one-sample t-testone proportion z-testtwo proportion z-testtwo independent samples t-testPaired t-testlinear regression

Determine whether the description corresponds to an observational study or an experiment. Give a brief explanation. Does anyone you know regularly take a low-dose aspirin? If so, it may be because of a randomized experiment conducted in the 1980s, the Physicians' Health Study. The study recruited 22,071 male physicians and randomly assigned half of them to take an aspirin every other day for about five years and the other half to take a fake aspirin pill instead. They found that the physicians who took the real aspirin had 44% fewer heart attacks than those taking the fake aspirin. Because the physicians were split into two groups randomly, the only difference between the groups should be the aspirin. Therefore, we can conclude that the difference in heart attack rates must be caused by aspirin. From this study, we can conclude that regularly taking a low-dose aspirin reduces the risk of a heart attack. a) Is this an observational or experimental study? [ Select ] b) Which statistical test is most appropriate to analyze the data in this study? [ Select ]