题目

利用钓鱼竿钓鱼的示意图如图所示，O为支点，F1是手对鱼竿的作用力，请画出：（1）鱼线对钓鱼竿拉力F2的示意图；（2）F1的力臂。 答案：解析:略—When is Linda's birthday?—_________.          [     ]A. Her is May fifthB. May the fifthC. She is on May fifthD. She is five years old