(11·贵港)计算4×(-2)的结果是
A.6
B.-6
C.8
D.-8
答案:D
分析:根据有理数乘法法则进行计算,同号得正,异号得负.
解答:解:4×(-2)=-8.
故选D.
当在架上,模拟下颌做前伸运动时,要求排列的全口义齿()
A.前、后牙均不接触
B.前牙接触,后牙不接触
C.前牙不接触,后牙接触
D.前、后牙均保持接触
E.全口义齿不要求达到前伸时的咬合平衡
There is no doubt ______ everyone will unite and work for better days.
A.whether
B.that
C.what
D.how