已知6，7，8，9，x的平均数是8，则x=（ ）。
10
He has known the truth. Therefore, there is no ____ to keep it a secret
A．chance
B．doubt
C．possible
D．likely
一个工厂一月份产铜152.7吨，二月份比一月份多生产94.5吨，三月份比二月份少产105.1吨，三月份产铜多少吨？
