石膏线条属于()
A.纺织品装饰材料
B.陶瓷装饰材料
C.无机矿物装饰材料
D.木质装饰材料
参考答案:C
函数y=x2(x>0)的图像在点(ak,ak2)处的切线与x轴交点的横坐标为ak+1,k为正整数,a1=16,则a1+a3+a5=( )。
95. For a big order from Southeast Asia the boss _____ the workers to work extra two hours and promised to double their overtime pay(加班费).
A.demanded
B.required
C.needed
D.Had