登月火箭关闭发动机在离月球表面112km的空中沿圆形轨道运动,周期是120.5min,月球的半径是1740km,根据这组数据计算月球的质量和平均密度。
,
He thought the picture was of a little ______, so he let me have it for five pounds.
A.cost
B.value
C.price
D.money
在业主制企业中,产权主体是唯一的。()