And so there you go, that is our critical value, 2.160. So this, so this part right over here, so this is going to be two, let me do that in a darker color. This is going to be 2.160 times, what's our sample standard deviation? It's 50 over the square root of n, square root of 14. So all of our choices have the 700 there. So we just need to figure out what our margin of error, this part of it, and we could use a calculator for that. Okay, 2.16, I could write a zero there, it doesn't really matter, times 50 divided by the square root of 14, square root of 14.