同学们在体育活动及测试中涉及到了许多物理知识,下列说法正确的是( )
一块底和高分别为88米和43米的平行四边形的土地,如果平均每平方米可种植小树苗3棵,那么共可种植____棵小树苗.
如图所示,同种材料制成的实心圆柱体A和B放在水平地面上,高度比hA:hB=2:1,底面积之比SA:SB=1:2,则它们对地面的压强之比pA:pB=____。
Xiao Li was supposed __________ her homework before nine o'clock. But she couldn't.