The Bureau of Administration is concerned with high levels of employee absenteeism. Last year, the average employee missed 12.8 workdays. This year, there is an experimental program in which the agency pays employees for each sick day or personal day that they do not use. A preliminary survey of 20 persons reveals a mean of 8.7 days missed and a standard deviation of 4.6. Present a hypothesis and a null hypothesis, and evaluate them. State a conclusion in plain English.