10 L 1 mol/L Al₂(SO₄)₃溶液中含有SO₄^2-的物质的量浓度是(    )

-- ____ me the rice, please.

-- Here you are.

如图所示，质量为M，长度为L的小车静止在光滑的水平面上，质量为m的小物块，放在小车的最左端，现用一水平向右的恒力F始终作用在小物块上，小物块与小车之间的滑动摩擦力为f，经过一段时间后小车运动的位移为x，此时小物块刚好滑到小车的最右端，则下列说法中正确的是（   ）

阅读理解A
    I'm Linda．I can't find my keys．I lost them this morning．There is a Lost and Found box in our classroom．My keys may (可能)be in the box．
    Oh, there are many things in the box．This is a pencil box．What color is it? It's yellow．That is a white eraser．And what's that? It is a watch．A picture of a CD is on it．It's Sara's．Wow! I find my keys．One is to my classroom，and the other (另一个)is to my house．That green cup is Jack's．This baseball is his，too．I will(将)ask him to take his things．Three rulers, two pencils and two nice pens are also in the box．Whose are they? I don't know．
根据材料内容判断正误。

肌肉注射时，药液进入人体后经过的一般途径是