![](https://static.youtibao.com/asksite/comm/h5/images/m_q_title.png)
[单选题]
一块长方形土地的长为250米,宽为200米。这块土地的面积是()公顷
A.0.05
B.5
C.50
D.500
![](https://static.youtibao.com/asksite/comm/h5/images/m_q_a.png)
B、5
![](https://static.youtibao.com/asksite/comm/h5/images/solist_ts.png)
A.0.05
B.5
C.50
D.500
B、5
A.1:100
B.1:2000
C.1:1000
D.1:200
如图6-5所示,一块高为a,宽为b的长方形钢板放在边长为c的立方体的冰块之上,钢板两端分别各挂上一质量为m的重物.整个系统及周围环境均在0℃温度下.
A.4200
B.4000
C.3000
D.2800