Which sentence supports the claim that scratch- resistant plastic is essential to space travel? A substantially cheaper, but they also had problems. The plastic lenses broke less frequently and were B The U.S. government has mandated that all prescription lenses be made of plastic instead of glass. C Astronauts in the depths of space absolutely cannot afford a scratch on the visors of their helmets. D not made of actual glass. There's a funny thing about your eyeglasses -they're