1. Notice the effect on power of changing the true mean to 60. Look at the distributions to find the area that represents power.
   
   
2. Change the sample size and notice its effect on the cutoff point and on power.
   
   
3. Change the population standard deviation (sd) and notice its effect on the cutoff point and on power.
   
   
4. Compare the power of one-tailed and two-tailed tests. What is the power for each when the true mean is 55. What about 45? (The one-tailed tests are based on the expectation that the population mean is > 50.)
   
   
5. Set the value of the true mean to 50. Does power make sense in this situation?
   
   
6. Determine the effect of the significance level on the red and blue distributions. On what (in addition to power) does it have its effect?