statistics help!!too

College is concerned that out of state students may be receiving lower grades than local students. Two independent random samples have been selected: 165 observations from population 1 (Out of state students) and 177 from population 2 (local students). The sample means obtained are X1(bar)=86 and X2(bar)=87. It is known from previous studies that the population variances are 8.1 and 7.3 respectively. Using a level of significance of .01, is there evidence that the out of state students may be receiving lower grades? Fully explain your answer.