User contributions
- 02:11, 11 October 2013 (diff | hist) . . (+19) . . 121: Balloon (→Explanation)
- 05:34, 21 July 2013 (diff | hist) . . (-1) . . 300: Facebook (→Explanation)
- 05:21, 21 July 2013 (diff | hist) . . (+5) . . 536: Space Elevators (→Explanation)
- 19:39, 13 July 2013 (diff | hist) . . (+1) . . 904: Sports (→The word in the text "were" should be "where". (third paragraph, starting "Third, a weighted...")