Waves and Materials Practice Test

A student stacks several identical clear plastic sheets, one on top of another, and looks through them at a page of text. The text is still readable, but it looks dimmer as more sheets are added. Which explanation best matches this observation?​

A flashlight is shined at a sheet of cardboard. On the other side of the cardboard, the wall stays dark and a shadow forms. Which statement best describes the cardboard and what it does to visible light?