母线与刀闸各部的允许温度为（）℃，母线接头允许最高温度为（）℃，封闭母线最高允许温度为（）℃，其外壳允许最高温度为（）℃
参考答案：70；105；90；65
梁桥和拱桥重力式桥墩有哪些类型？重力式桥墩受力和构造特点？
The CPU does not have to look (66) all of RAM to find the spot it needs. But RAM only (67) the data temporarily. As soon as you switch the computer (68) , all that information disappears from the RAM. When you switch the computer on again, the RAM is (69) , and ready (70) a new program and new data.
（66）处填（）。
A．on
B．through
C．for
D．down upon
