答案:B
Now that you are a college student, you should learn to be ________ of your parents' help.[ ]
A.energetic
B.obvious
C.independent
D.religious
天文学家发现某恒星周围有一颗行星在圆形轨道上绕其运动,并测出了行星的轨道半径和运行周期.由此可推算出 ( )
A.行星的质量
B.行星的半径
C.恒星的质量
D.恒星的半径