A. 变软 B. 变硬 C. 不变 D. 先变硬,和变软
A. Xi’an YouDian University B. Xi’an University of Postsand Telecommunications C. Xi’an Universityof Mobileand Electronics D. Xi’an University of Computer and Digital
A. 刘华清 B. 罗阳 C. 钱学森 D. 邓三瑞
A. 正确 B. 错误