A researcher wishes to estimate the number of households with two computers. How large a sample is needed in order to be 98% confident that the sample proportion will not differ from the true proportion by more than 2%? A previous study indicates that the proportion of households with two computers is 20%.

Aresearcher believes increased perceived control influence the well-being of residents at a nursing home. to test this , she allowed one group of residents to have control over their daily lies, (where to eat etc) . the other group of 5 residents had these deceisions made by staff. the resident's feelings of well-being were measured on a 10 point scale at the end of a one month trial period. is there a difference on well-being?