当悉尼的白昼逐渐变长的时候,太阳直射点可能[ ]
A.正从北回归线向南移动
B.正从南回归线向北移动
C.正从赤道向北回归线移动
D.正从南回归线向赤道移动
答案:A
锥形分配切削量的丝锥叫()逆转。
The VDR system is designed to operate()once it is set up correctly.There is no user interaction.
A.automatically
B.accurately
C.promptly
D.conspicuously