Hello, I need help navigating statkey for a few questions and I also need help with the following: (a) Find a 95% confidence interval for the

(a)  Find a 95% confidence interval for the difference between the average tensile strength of Supplier A's cotton and the average tensile strength of Supplier B's cotton. Use the formula .

According to my personal calculations, the diff in mean is 2.405

2.405+-(2*2.119)=(-1.833,6.643)