18:15=24:20=3025=48÷40=1.2.
故答案为:15,24,30,48.
— _______________ the pen?
— It's in your pencil-case. [ ]
A. Where
B. What's
C. Where's
已知精矿粉平均配比为70%,每米皮带上料量需用110kg,皮带速度96m/min试问全年需精矿粉多少吨?