题目

下图是某电热水壶的铭牌.要将1L 20oC的水烧开(标准大气压),此壶需要正常工作3min20s。求: 1.    水吸收的热量? 2.    电水壶消耗的电能? 3.    热效率?                            XX牌电水壶 额定电压220V 额定功率2000W 电源频率50Hz 容量1.2L 答案:336000J    400000J   84%-Her face _________ great joy when Mrs.White knew that her son had been admitted to Harvard.-Which of the following is wrong?A.suggestedB.expressedC.explainedD.showed
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