题干

如图,位于竖直水平面内的光滑轨道由四分之一圆弧ab和抛物线bc组成,圆弧半径Oa水平,b点为抛物线顶点。已知h=2m,,s=s=2m。取重力加速度大小g=10m/s2。
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同类题3

诗词鉴赏。

阅读《诗经》的两首诗歌,完成题目。
                                                              关关雎鸠,在河之洲。窈窕淑女,君子好逑。

                                                              参差荇菜,左右流之。窈窕淑女,寤寐求之。  
                                                              求之不得,寤寐思服。悠哉悠哉,辗转反侧。

                                                              参差荇菜,左右采之。窈窕淑女,琴瑟友之。  
                                                              参差荇菜,左右芼之。窈窕淑女,钟鼓乐之。        

                                                                                                ——《关雎》
                                                             蒹葭苍苍,白露为霜。所谓伊人,在水一方。  

                                                             溯洄从之,道阻且长。溯游从之,宛在水中央。  

                                                             蒹葭凄凄,白露未晞。所谓伊人,在水之湄。  

                                                             溯洄从之,道阻且跻。溯游从之,宛在水中坻。  

                                                             蒹葭采采,白露未已。所谓伊人,在水之涘。  

                                                             溯洄从之,道阻且右。溯游从之,宛在水中沚。
                                                                                              ——《蒹葭》

同类题5

任务型阅读,请阅读下面这篇文章,根据所提供的信息,完成下面的信息卡。

    We often dine out with others, but do you know some basic etiquette (礼节)? If you behave well at the table, it will make your partners happy. But if you don't know how to behave yourself, you will feel embarrassed. Here are some tips for the table etiquette.

    When helping a woman pull her chair to the table, hold it and guide it. Don t shove(碰撞)it against the back of her legs.
     If you're seated at a table with eight or fewer guests, wait for everyone to be served and for the hostess(女主人) to begin eating before you dig in. At a long banquet table, it's OK to start when several people are seated and served.

    If you prefer not to have wine while dining out, don't turn your glass upside down, and don t make a big deal of saying you don't drink. Simply place your fingertips on the rim(边缘) of the glass and say" Not today, thanks."

    When you excuse yourself to go to the restroom, just say" Please excuse me."

    When out with friends or family—even at a fancy restaurant –it's OK to ask for your leftovers(吃剩的饭菜) to be wrapped. But don't do it at a business lunch or dinner.

Information Card

The feeling you may get if you don't behave well at the table

____

The number of the guests when waiting for everyone to be served

____

The reason why you place your fingertips on the rim of the glass

____

The time that don't ask for your leftovers to be wrapped

____

The number of suggestions for the table etiquette

____