The amount of available disk space on a digital video recorder changed from 81% to 9% after recording 12 episodes of a show. Each episode requires the same amount of disk space. Which statement is true? The change in available disk space is 6% per episode. The change in available disk space is −6% per episode. The change in available disk space is 7.5% per episode. The change in available disk space is −7.5% per episode.