题型:选择题 —It's terribly cold today, isn't it?—Yes. yesterday.[ ]A. So it isB. So is it C. So was it D. So it was 查看答案
题型:问答题 已知水的比热容为4.2×103J/(kg•℃),则质量为2kg的水,温度由25℃降低到20℃放出的热量是( )A.4.2×104JB.2.1×105JC.1.68×105JD.3.78×105J 查看答案