知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。 RAND is actually a study Business that develops solutions to general public coverage problems to help make communities through the earth safer and more secure, healthier and more prosperous. RAND is nonprofit, nonpartisan, and dedicated to the public interest. Considering the fact that its launch in November https://friedrichc951fgh9.webdesign96.com/profile