题目

阅读理解Wecan achieve knowledge either actively or passively (被动地). We achieve it actively bydirect experience, by testing and proving an idea, or by reasoning. Weachieve knowledge passively by being told by someone else. Most of the learningthat takes place in the classroom and the kind that happens when we watch TV orread newspapers or magazines is passive. Conditioned as we are to passivelearning, it's not surprising that we depend on it in our everydaycommunication with friends and co-workers. Unfortunately,passive learning has a serious problem. It makes us tend to accept what w10．如图甲所示是一台单缸四冲程汽油机工作状态示意图，由图甲可以看出，此时它所处在做功冲程，其能量转化情况与乙（选填“乙”或“丙”）图相同；若飞轮转速是1200r/min，则汽油机每分钟对外做功10次．