A researcher conducted an Internet survey of 300 students at a particular college to estimate the average amount of money students spend on groceries per week.The researcher knows that the population standard deviation, sigma: , of weekly spending is $25.The mean of the sample is $85.What is the margin of error if the researcher wants to be 99% confident of the result?

Please choose one:

a.2.83

b.2.81

c.2.82

D.2.84

to.2.80