如图所示实验装置,甲重16N,乙重12N,静止时不计弹簧测力计自重,则甲物体所受的合力为( )
A:16N
B:0N
C:28N
D:4N
下列各项中,对情节陈述正确的一项是 ( )
社会保障制度的核心是( )
—Oh, did you? I am sorry but I switched off my phone early yesterday evening.
读黑龙江省略图,下列说法正确的是( )