一物体沿半径为R的圆周运动一周，其位移的大小和路程分别是（　　）。

为贯彻落实党的十七大提出的“逐步实行城乡相同人口比例选举人大代表”的要求，今年3月召开的全国人大三次会议审议通过了《选举法修正案》，选举法的修正有利于更好地保证城乡人民享有平等的选举权。上述材料体现的政治常识道理是（ ）
①坚持党的领导、人民当家作主和依法治国的有机统一    
②体现了以人为本是科学发展观的第一要义
③党的主张通过法定程序上升为国家意志   
④选举法的修改有利于统筹城乡发展、构建和谐社会

核电站中可用硼酸（H₃BO₃）吸收中子，阻断核辐射．硼酸中硼元素的化合价是（   ）

如图，直线a，b被直线c所截，∠1与∠2的位置关系是（  ）

根据短文理解，完成各题任务。
C
    Sally is an English girl. She is my English teacher, Mrs. Brown's daughter. She is only five years old. (A)She can't go to school. She likes playing ping-pong.
    Her favorite ping-pong player is Zhang Yining. Sally is in the ping-pong club. She goes to the ping-pong club every day. She plays ping-pong for two hours there.
    Sally has a sister. Her name is Maria. She is in our class. She likes running. She runs with her mother every morning. (B)她最喜欢的赛跑明星是刘翔. Maria says she wants to be a running star like Liu Xiang.