Physics:Newton's Apple（24）
On this episode of Newton's Apple， we shall find answers to the questions: First， what will happen to my letters once I deposit them into a mailbox? Second， how can some gemstones have different colors? At the end of today's show， we will tell you how you bring your curiosity and camera to work by joining next year's contest.
- Added：2006
- Country：America
- Duration：30
- Time of update：2011/8/16 10:29:09