如图,已知甲、乙、丙三个扇形的面积比为3:4:5,分别求出它们圆心角的度数.
12 ÷ 18=____ 15 ÷ 25=____
he comes tomorrow, I shall ask where he has been.
简便计算
4.75﹣9.63+8.25﹣1.37
81.5×15.8+81.5×51.8+67.6×18.5
99999×26+33333×22.