8-4____3
7+2____10
体积相同的两物体a、b,如图所示,都浸没在水中,则两物体受到水对它们向上和向下的压力差的关系是( )
如图,直线a∥b,直线c是截线,如果∠1=50°,那么∠2等于( )
Danny can't run fast. He is _______.