【单选题】The Internet is playing a ________ role in our life today.
【单选题】For urban areas this approach was wholly inadequate
【单选题】对于万有引力定律的表达式 下列 说法中正确的是 ( )
C.
两物体受到的引力总是大小相等的,而与 m 1 、 m 2 是否相等无关
D.
两物体受到的引力总是大小相等、方向相反,是一对平衡力
【简答题】已知 IP 地址是 141.14.72.24 ,子网掩码是 255.255.192.0. 试求网络地址。( )
【单选题】Earth scientists have come to understand that climate______.
A.
is going through a fundamental change
B.
has been getting warmer for 10 000 years
C.
will eventually change from hot to cold
D.
has gone through periodical changes
【单选题】对于万有引力定律的表达式F=G ,下列说法中正确的是( )。
C.
两物体受到的引力总是大小相等的,而与 m 1 、 m 2 是否相等无关
D.
两物体受到的引力总是大小相等、方向相反,是一对平衡力
【简答题】Word Building 1. The loan (able) Jan to buy the house. (Para. 2) 2. You are expected to be an active (participate) . (Para. 2) 3 . The president's (popular) has declined considerably. ( Para. 4 ) 4. S...
【单选题】下列说法中正确的( )
A.
万有引力定律只适用于两个质点间万有引力大小的计算
B.
据表达式F= ,当r趋近于零时,万有引力趋近于无穷大
C.
在开普勒第三定律 =k中,k是一个与中心天体有关的常量
D.
两物体间的万有引力总是大小相等、方向相反,是一对平衡力