下图是制作临时装片的几个步骤,正确的操作顺序是( )
A:①②③④
B:④③②①
C:④②①③
D:②③④①
属于营养繁殖方式的是( )
已知正六边形ABCDEF的边长为1,则AB→(CB→+BA→)的值为( )
_______the exam, we'll say good-bye to our dear teachers, classmates as well as ourbeautiful school.