S1, our sample standard deviation for group 1 is 4.67. We wrote it right here as well. It's 4.67 and 4.04. So this is 4.67, and this number right here is 4.04. The s is 4.67, we're going to have to square it, and the s2 is 4.04, we're going to have to square it. So let's calculate that. So we get, we're going to take the square root of 4.67 squared, divided by 100, plus 4.04 squared, divided by 100, and then close the parentheses, and we get.617.