A November 2007 Gallup Poll of 1004 adults found that 572 are satisfied with the total cost they pay for their health care. The announced margin of error is plus or minus 3 percentage points. The announced confidence level is 95%.
a. What is the value of the sample proportion p who so they are satisfied with the total cost they pay for their health care? Explain in words what the population parameter p is in this setting.
b. Make a confidence statement about the parameter p.