1. The length of time in minutes required to complete a series of physical therapy exercises is normally distributed with a mean of 70 minutes and a standard deviation of 12 minutes. What percent of patients can be expected to require more than 70 minutes to complete the series?
A. 1%
B. 18%
C. 22%
D. 50%
2. At a college, a coefficient of correlation of -0.70 was found between the number of high-school activities offered and the number of drug-related suspensions. What percent of the total variation in the drug-related suspensions is explained by the variation of factors other than college activities?
A. 49%
B. - 51%
C. Can't be determined with the given information
D. None of the above
3. Suppose 1,000 of the 2,000 school professors oppose the US policies in Europe. Using the 0.95 degree of confidence, the interval estimates for the population proportion is
A. about 0.5 to 0.8.
B. between -1 and +1.
C. between 0 and 1.
D. none of the above.
4. You have used the significant level of 0.01 to estimate the average hours of television viewing for the Az students. What is the chance that our interval estimate does not contain the true population mean?
A. 99%
B. 10%
C. 100%
D. 1%
E. None of the above