In a sample of 55 electric motors, the average efficiency (in percent) was 85 and the standard deviation was 2. The claim is made that the mean efficiency is greater than 84.582%. With what level of confidence can this statement be made

1. suppose that scores on a knowledge test are normally distributed with a mean of 71 and a standard deviation of 6. a. label the curve: show the mean and the value at each standard deviation: b. if angelica scored a 76 on the test, what is her z-score? (draw her score on the curve above and label) c. what percent of students did angelica score higher than? how can you tell? d. if 185 students took the test, how many students scored higher than angelica?