Before it was a defined quantity, separate groups of researchers independently obtained the following five results (all in km s1 ) during experiments to measure the speed of light c: 299795 5 , 299794 2 , 299790 3, 299791 2 , 299788 4

Determine the best overall result which should be reported as a weighted mean from this set of measurements of c, and find the uncertainty in that mean result.