Final answer:
The mean score on the calculus exam is 74.5. To find the percent of scores between 72.5 and 75.5, calculate the z-scores for both values and refer to the standard normal distribution.
Step-by-step explanation:
The mean score on the calculus exam is given as 74.5. Therefore, the correct answer to the question 'What is the mean score on the calculus exam?' is b) 74.5.
Now, to determine what percent of the scores are in the 72.5 and 75.5 range on a normally distributed exam with mean 74.5 and standard deviation 1.0, you would need to calculate the z-scores for 72.5 and 75.5 and then consult the standard normal distribution table (or use a calculator with normal distribution functions) to find the probabilities corresponding to these z-scores. The z-score is calculated using the formula (X - mean) / standard deviation, where X is the value in question.
For 72.5, the z-score would be (72.5 - 74.5) / 1.0 = -2.0. For 75.5, the z-score would be (75.5 - 74.5) / 1.0 = 1.0. The probability from the standard normal distribution table between these z-scores gives the percent of scores within this range.