The atmosphere is as much a part of the earth as __its soils and the water of its takes, rivers and oceans.A. are
A. are
B. is
C. do
D. has
Our company is ___ of other makers of spare parts for the airplane.
A. in advance
B. ahead
C. abreact
D. in front
设容量n=10的样本观察值为（8、7、6、9、8、7、5、9、6、5），则样本均值=________,样本方差=_________.
A. 7,2
B. 7,20/9
C. 70/9,2
D. 70/9,20/9
1、新民主主义经济纲领中极具特色的一些内容是：
A. 没收地主阶级土地归农民所有
B. 没收官僚垄断资本归新民主主义国家所有
C. 保护民族工商业
D. 发展生产、保证供给
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