静止的水平桌面上的墨水瓶，以下说法中正确的是（ ）
A．墨水瓶受到的重力和桌面受到的压力是一对平衡力
B．墨水瓶受到的重力和桌面受到的支持力是一对平衡力
C．墨水瓶受到的支持力和桌面受到的压力是一对平衡力
D．桌子受到的重力和桌面受到的支持力是一对平衡力
A、墨水瓶受到的重力和桌面受到的压力，两个力的方向相同且作用在两个物体上，不符合二力平衡条件，故A不正确；
B、墨水瓶受到的重力和桌面受到的支持力，两个力的大小相等、方向相反、作用在同一直线上、作用在同一个物体上，符合二力平衡条件，故B正确；
C、墨水瓶受到的支持力和桌面受到的压力，两个力的大小相等、方向相反、作用在同一直线上、作用在同两个物体上，符合相互作用力的体积，故C不正确；
D、桌面受到的支持力等于桌子的重力和墨水瓶重力之和，所以桌子受到的重力和桌面受到的支持力大小不相等，故D不正确．
故选B．
完形填空（共10小题；每小题1分，满分10分） 阅读下面短文，从短文后所给各题的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项。 Do you think of your parents? “Yes, of course.” You may answer. Maybe you buy a present for your mother on Mother’s Day, and you give your father _ 小题1:_ 0n Father’s Day, too. Then 小题2:__the other days of a year? Always remember to think of your parents, not just 小题3: some important days. I have a friend who lives _ 小题4:_.because her parents live in another city. One day I went to visit her. We had a nice chat. Then she wanted to 小题5: a telephone call. She dialed the number, but then she put the phone down. After about ten 小题6: .she dialed the number again. “Hi, Mum...” Later I asked, “why did you dial the number 小题7:_?”She smiled.“ because my parents are old. They can't get close to the telephone 小题8:_.I always do so when I call them, I just give them enough 小题9:___to answer the call.” My friend is a good girl . She is always thinking about her parents. What do you think of this? I think: we should do some small things for our parents and make them 小题10:__every day.
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