Scores on a standardized exam are known to follow a normal distribution with a standard deviation of o = 8. A researcher randomly selects 84 students and finds their mean exam score to be I = 78. How confident are you that the mean score for all students taking the exam is in the interval (76.702, 79.298)? *Include 2 decimals places in your final answer* Confidence Level:

Ali scores 70 on Calculus-1 course with a class mean of 68 and a standard deviation of 2, and he scores 68 on Introduction to Operating with a class average of 60 and a standard deviation of 2. In which test did he perform well? Explain

A researcher measures the amount of sugar in several cans of the same soda. The mean is 39.01 with a standard deviation of 0.5. The researcher randomly selects a sample of 100.  If the researcher wants to find the probability that the sum of the 100 values is greater than 3,910, what is the mean and standard deviation that should be used? mean=??? standard deviation=????

A company produces steel rods. The lengths of the steel rods are normally distributed with a mean of 239.7-cm and a standard deviation of 0.8-cm. For shipment, 5 steel rods are bundled together.Find P58, which is the average length separating the smallest 58% bundles from the largest 42% bundles. P58 = -cmEnter your answer as a number accurate to 2 decimal place. Answers obtained using exact z-scores or z-scores rounded to 3 decimal places are accepted.