文档介绍：第一章 (20题)                                                                                                                                                       、,、强辐射、,                                              ,                                ,:大→小→:大→小→:短→长→:快→慢→                                (30°E、20°N),,,,                                                          ,能形成物影、                              ,又是太阳系中独特的一员,她生机勃勃,生活在其上的人类不断繁衍生息,即将迎来太空时代。请回答14~18小题:,,,,,,向宇宙空间