Which sentence shows where a comma should be placed to indicate words left out of an elliptical sentence?

thomas rides over the larger hills at the bike park; i, over the smaller ones.

thomas rides over the larger hills at the bike park; i over, the smaller ones.

thomas rides over the larger hills at the bike park; i over the smaller, ones.

thomas rides, over the larger hills, at the bike park; i over the smaller ones.

Consider the title and souce of the following articles. which one is most likely to exhibit a bias? (a) how to roast beef," by the food editor of a magazine (b) americans experiencing greater fatigue than previous generations, " by a harvard researcher (c) "americans' worsening eyesight not related to computer screen usage," by the public relations director of a major computer manufacturer (d) "sharing the burden: a history of cooperation," by a college professor