As shown in the following illustration．There is some water in the sealed container and the height from the bottom to the surface of the water is 10cm，if we put the container upside down，What’s the height（cm） from the surface of the water to the bottom？ 如图所示，在密封的容器中装有一些水，水面到底部的高度是10厘米，如果将这个容器倒过来，请你求出水面到底部的高度是多少厘米？
You have 3 weights：1 kg，3 kg and 9 kg as well as an equal arm balance，as shown．How many different weight objects can you weigh with these three？[Remember the weights may be placed on either side] 翻译：你有3个砝码：1公斤、3公斤和9公斤，以及一个托盘天平，你可以称出多少个不同的重量？（记住砝码可以放在天边两边的任意一边）
You have 3 weights：1 kg，3 kg and 9 kg as well as an equal arm balance，as shown．How many different weight objects can you weigh with these three？[Remember the weights may be placed on either side] 翻译：你有3个砝码：1公斤、3公斤和9公斤，以及一个托盘天平，你可以称出多少个不同的重量？（记住砝码可以放在天边两边的任意一边）
There is 1000grams of alcohol solution with the concentration of 15% in the bottle，and now we pour 200grams of alcohol solution A and 400grams of alcohol solution B respectively，the concentration turns to 14%．the concentration of A is twice as much as the concentration of B．What’s the concentration of alcohol solution A？ 瓶中装有浓度为15%的酒精溶液1000克，现在又分别倒入200克和400克的A、B两种酒精溶液，瓶中的浓度变为14%．已知A种酒精溶液是B种酒精溶液浓度的2倍，那么A种酒精溶液的浓度是多少？
As shown below，the area of the parallelogram ABCD is 54cm2，E，F trisect CA and BA，the area of the shadow is
As shown in the following illustration．There is some water in the sealed container and the height from the bottom to the surface of the water is 10cm，if we put the container upside down，What’s the height（cm） from the surface of the water to the bottom？
如图，一个边长是5厘米的正方体，是由125个边长为1厘米的小正方体组成的．P为上底面ABCD的对角线的交点．分别用通过P、E、F三点的平面，P、F、G三点的平面，P、H、G三点的平面，P、H、E三点的平面把正方体切开，则最后剩下的立体图形中包含
如图，正方形ABCD的边长为8厘米，E，F是边上的两点，且AE=3厘米，AF=4厘米，在正方形的边界上再选一点P，使得三角形EFP的面积尽可能大，这个面积的最大值是
如图，正六边形ABCDEF的面积是6平方厘米，M、N、P分别是所在边的中点，则三角形MNP的面积是
如图，在A、B位于直线L的同侧，在L上找一点P，使得AP+PB最短．
如图，半圆周上任意一点P，连接AP、BP，∠APB的度数是（ ）
小学二年级奥数天天练：分别计数P，S，C．
在边长为6厘米的正方形ABCD内任取一点P，将正方形的一组对边二等分，另一组对边三等分，分别与P点连接，求阴影部分面积．