力偶对任一轴上的投影代数和(),力偶对其作用平面内任一点之矩恒等于()。
参考答案:等于零、力偶矩
In winter people usually keep flowers in their houses to _____ them from the cold. [ ]
A. produce
B. provide
C. protect
D. plant
南岛语系属于粘着型语言,主要构成词和构形手段是词根添上附加成分和词根的重叠或部分重叠。