多囊卵巢综合征()
A.脓样白带
B.下腹剧痛
C.下腹部肿块
D.闭经
E.慵经
参考答案:D
—Do you know the Water Cube at all?
—No, this is the first time I ________ here.
A.have been
B.came
C.was
D.am going
将实心正方体木块轻轻地放入一侧倾斜放置且装满水的大烧杯内,该木块质地均匀,边长为5厘米,待木块静止时,从杯中溢出75克水,如图所示,求:
(1)木块受到的浮力
(2)木块的密度
(3)木块下表面受到的水的压强