在数轴上与3所对应的点的距离为3的点所对应的数是______.
如图:在数轴上与3所对应的点的距离为3的点所对应的数是0和6.
Parents of a child with cystic fibrosis demonstrate knowledge of the effects of hot weather on their child when they state that hot weather is hazardous because the child has which of the following
A. Poor ability to concentrate urine.B. Little skin pigment to prevent sunburn.C. Poorly functioning temperature control center.D. Abnormally high salt loss through perspiration.
A.机械效率越高,机械做功一定越快
B.做功越多的机械,机械效率一定越高
C.功率越大的机械做功一定越多
D.做功越快的机械,功率一定越大