题目

把物体放在空气中冷却,如果物体原来的温度是θ1,空气温度是θ0,t分钟后物体的温度θ=θ0+(θ1-θ0),现有60℃的物体放在15℃的空气中冷却,当物体温度为35℃时,冷却时间t=______________分钟. 答案：2解:35=15+(60-15),()t==()2,t=2.或35=15+(60-15),()-t==()-2,∴t=2. ---I think Peter is coming to our house.         ---If he        , we’ll be very happy.       A. come         B. comes       C. came        D. will come