So to estimate the standard deviation of this, we will use our sampling standard deviation as our best estimate for the population standard deviation. So we could say, now remember, this is an estimate. We cannot come up with the exact number for this just from a sample, but we can estimate it. Because this is our best estimator for this standard deviation, and if we divide it by 10, we will have our best estimator for the standard deviation of the sampling distribution of the sampling mean. So remember, this is just an estimate. So you kind of have to take everything after this point with a little bit of a grain of salt. So it's going to be roughly equal to, or an estimate of it is going to be 0.5.