欧洲联盟与北美自由贸易区、亚太经济合作组织的不同点是．

细菌蛋白质在极端环境条件下可通过肽链之间的二硫键维持稳定．已知不同的多肽产物可因分子量不同而以电泳方式分离．如图所示是一个分析细菌蛋白质的电泳结果图，“﹣”代表没加还原剂，“+”代表加有还原剂，还原剂可打断二硫键，“M”代表已知分子量的蛋白质，右侧数字单摆蛋白质或多肽的相对分子量，根据如图所示的结果，下列哪个图案最能代表该细菌原本的多肽结构（注意：“﹣”代表二硫键）（    ）

在横线上填上恰当的词语。

____的嘴脸  ____的波状  ____的富翁

____的傻瓜  ____的变化  ____的繁琐

根据材料内容，选择正确答案。

    Tom went to see his grandparent with his father. In the train Tom often put his head out of the window. His father said, "Tom, don't put your head out of the window." But Tom went on putting his head out of the window.

    His father took Tom's hat quietly and hid it behind his back and said to Tom, "You see your hat is gone." Tom was afraid. His father said, "Well, whistle(吹口哨) once. Maybe your hat will come back." Tom whistled. His lather put his hat on Tom's head quickly. "Oh! It's wonderful!" Tom laughed and said. He quickly took his father's hat and threw it out of the window. "Now it's your turn to whistle, Dad!" he said happily.

有一量杯,它的最大刻度值是100cm³,最大刻度线距离杯底的高度为h,则在高度为h/2处的刻度线表示容积的数值是（  ）