T8A Check for Understanding Name #1-3: Determine if each scenario is an observational study, survey, or experiment. Explain: 1. Does reducing screen brightness increase battery life in laptop computers? To find out, researchers obtained 30 new laptops of the same brand. They chose 15 of the computers at random and adjusted their screens to the brightest setting. The other 15 laptop scree were left at the default setting (moderate brightness). Researchers then measured how long each machine's battery lasted. experimental