A:8π
B:6π
C:4π
D:π
—They went to the hospital to______________ the sick kids.
用来擦拭显微镜头污点的是( )
已知角α的终边与以坐标原点为圆心,以1为半径的圆交于点P(sin2π3,cos2π3),则角α的最小正值为( )