一般来说，人眼就能察觉出颜色变化时，波长变动（）。
A.3nm～5nm
B.1nm～2nm
C.10nm～12nm
参考答案：B
. I look on it as a good opportunity to ________ fresh skills and broaden my knowledge.
A．acquire
B．require
C．accept
D．receive
轴向位移增大的现象有哪些？
