What was the main cause of the Second World War?()
A. The main cause was big power struggle for control of the world.
B. It was the worldwide economic crisis.
C. It was the military expansion of Japan,and Germany.
查看答案
下列选项中,哪种环境最适宜珊瑚生长?()
A. 水流缓慢的海域
B. 水流强劲的海域
C. 水流静止的海域
D. 水流回旋的海域
适合于低点阵的针式打印机输出和计算机屏幕显示的字形技术是()
A. 点阵字
B. 矢量字
C. 曲线字
尾矿水在坝体、坝肩和坝基土中受重力作用总是由高处向低处渗透流动。
A. 正确
B. 错误