The U. S Census Bereau reported that the mean annual salary in 2002 was $51,194 for an individual whose highest degree was a bachelor's. A government economist believes that the mean anual salty for individuals whose highest degree is a bachelor is different today. She obtains a random sample of 300 employed adults whose highest degree is a bachelors and determine the mean annual salary to be $55,988 with a population standard deviation of $26,855. Text the economists claim at the a=0.05 significance. Fine the z-score. HELP