You shouldn't need more than an hour or so to answer the questions. When we applied, Davidson used paper applications and I hand-wrote one or two paragraphs per question in the space provided. I don't believe that an exhaustive history reaching back several years is necessary or even wise. I kept it short and sweet by avoiding everything that would have been obvious based on the rest of the application. Therefore, I made no mention of math or reading and only included anecdotes that might stand out among high ability cohorts. For example, I mentioned observing DS killing a high school game at age 7, which required swift application of the Amendments to factual scenarios to determine whether there were constitutional violations.
Good luck - you should be fine because those are high scores rather than borderline.
