1. Test scores on a Statistics final had a mean of 78 with a standard deviation of 16. Luisa earned a score of 82 on the final. Which of the following is the correct interpretation of her z-score?

1. Luisa's score is 0.25 points below the mean.
2. Luisa's score is 4 standard deviations above the mean.
3. Luisa's score is 0.25 standard deviations above the mean.
4. Luisa's score is 4 points below the mean.
5. The weights of the fish in a certain lake are normally distributed with a mean of 20 pounds and a standard deviation of 5 pounds. Round your answers to four decimal places.
6. What is the probability that a randomly selected fish weighs less than 18 pounds?
7. What is the probability that a randomly selected fish weighs between 14 and 24 pounds?
8. iii. Find the weight such that 15% of fish are heavier than it.

1. The annual amount of snowfall in a certain mountain range is normally distributed with a mean of 70 inches and a standard deviation of 8 inches.

i. What percent of years have a snowfall between 54 and 86 inches?

ii. What percent of years have a snowfall less than 62 inches or more than 78 inches?

1. In a study of whether speeding was a contributing factor, a random sample of 165 fatal car crashes resulted in a 95% confidence interval forppof (0.268, 0.324). Which of the following is the correct interpretation of the interval?
2. There is a 95% probability that the true proportion of fatal car crashes where speed was a contributing factor is between 0.268 and 0.324.
3. We are 95% confident that the true proportion of fatal car crashes where speed was a contributing factor is between 0.268 and 0.324.
4. We are 95% confident that the interval from 0.268 to 0.324 captures the proportion of all fatal car crashes where speed was a contributing factor.
5. We are 95% confident that the interval from 0.268 to 0.324 captures the proportion of fatal car crashes in the study where speed was a contributing factor.
6. 95% of the time, the interval from 0.268 to 0.324 captures the proportion of all fatal car crashes where speed was a contributing factor.