Hello! Some sample keys for the true or false three question test would be:
Keys are: False, False, False, True, True, True, False, False, True, True, True, False, False, True, False, True, False, True. False, True, True, True, True, False. Those are all the possible combinations for the answer key. (every 3 is a group). Hope this helps! Have a great day!
B. 95% confident the average concentration of PCBs in the water supply is between 2.9 ppb and 3.5 ppb
Step-by-step explanation:
You are given the total number of samples, the concentration of lead, and the standard deviation. The standard deviation represents how inaccurate the estimation of the concentration of lead in the drinking water. This means that there can only possibly be a 0.3 ppb error in the estimation. 3.2-0.3=2.9, and 3.2+0.3=3.5