If Z is a standard normal variable, find the probability.

7. The probability that Z lies between -0.55 and 0.55.

8. P(Z < 0.97)

Compute standard deviation.

9. An unknown distribution has a mean of 160 and standard deviation of 29. Samples of the size 32 are randomly drawn from the population. Compute standard deviation of the sampling distribution. Round your. answer to two decimal place.

Compute probability.

10. An unknown distribution has a mean of 192 and standard deviation of 38. Samples of the size 42 are randomly drawn from the population. Find the probability that the sample mean is greater than 187. Round your answer to four decimal place.

11. An unknown distribution has a mean of 668 and standard deviation of 96. Samples go the size 32 are randomly drawn from the population. Find the probability that the sample mean is between 649 and 688. Round your final answer to four decimal place. When solving the problem round your sample standard deviation to one decimal place.