Physics:Newton's Apple（31）
On this episode of Newton's Apple， we shall find answers to the questions: First， Kody Naff asked， "I wanted to go wild water rafting for years， but I just can't quite get the courage up. I know that making down the river safely has a lot to do with knowing how to read the rapids， can you explain what this means?" Second， Daniel Toronto asked， "I know people who have asthma and I would like to know what make it hard for them to breathe."
- Added：2006
- Country：America
- Duration：30
- Time of update：2011/8/16 10:36:49