A study suggests that about 80\%80%80, percent of undergraduate students are working at a job. Researchers plan to do a follow-up study with a new sample of students. They'll use the new data to make a one-sample zzz interval to estimate the proportion of students who are working at a job. The researchers plan on using a confidence level of 90\%90%90, percent, and they want the margin of error to be no more than \pm 1\%±1%plus minus, 1, percent. If we assume \hat p=0. 80 p ^ =0. 80p, with, hat, on top, equals, 0, point, 80, what is the smallest sample size required to obtain the desired margin of error?.