Avsnitt 40

Marc proposes to burn a hole through a piece of cardboard using a magnifying glass and the sun. It doesn't harm the cardboard, but Lisa and Trini get the message.REHASHED FROM THE PREVIOUS FOUR EPISODES: Trini discovers a boy whose vision was improved with a cornea transplant. Trini uses a prism to split white light into the color spectrum. Lisa witnesses an infrared camera. Marc learns that butterflies and flowers bear ultraviolet light . Trini visits an observatory whose telescope studies the sun. ANIMATION: How the eye sees.ADDITIONAL: Lisa examines lasers. Marc encounters a solar-energy research lab.