Mean annual salary offer for students graduating with degree in accounting in 2010 was $49,722. We sample 50 accounting graduates from 2011 and find the mean and standard deviation to be $49,850 and $3,300, respectively. Do the sample data provide support for the claim that mean salary offer for accounting graduates is higher in 2011 that 2010? Test at 5% level of significance. Construct a 95% CI for this mean