Help with a and b

"() One hundred students write a calculus test that is given every year. Their sample mean score and sample variance are 70-46 and 6.25 respectively. Find a 95%% confidence interval for the population mean score for this test A local news team visited Mcdonalds in the city of chicago & ordered Large fries at each location. One order included 86 fries while the Other came w / 100. Find a 90% confidence interval for the population mean number of fries in an order of Large fries from a Mcdonalds in Chicago