不等式组{#mathml#}$\left\{\begin{array}{c}\frac{1}{2}x+1\ge -3\\ x-2\left(x-3\right)>0\end{array}\right.${#/mathml#}的最大整数解为（　　）

如图所示，将一底面积为30cm²，高为10cm的长方体，悬挂在弹簧测力计上，在空气中称量时，弹簧测力计示数为5N．将物体完全浸没在某种液体中，物体下表面距液面20cm时，下表面所受液体压力为4.8N．g取10N/kg．求：

阅读下面短文，根据短文内容从每题所给的A、B、C、D四个选项中选出最佳选项。

Can plants eat people? Probably not, but there are many plants that eat meat. Some of them are big. And they can eat small animals. One famous meat-eating plant is Venus Flytrap(捕蝇草). 

Venus flytrap is a very strange plant. It grows in dry parts of the United States. Its leaves are like the pages of a book. They can open and close very quickly. Inside the leaves, there are three small hairs. If a fly touches one of the hairs, the leaf closes quickly， so the fly cannot get out. In about half an hour, the leaf presses the fly until it is dead. Then, the plant covers the fly and slowly eats it.

Why do plants do that? Most plants get what they need from the sun, the air, and the ground. In some places, the ground is very poor. It doesn't have all these important things, especially nitrogen (氮). Animal meat has a lot of nitrogen, so some plants eat meat to get what they need. Let's hope that bigger plants don't get the same idea!