下列叙述中正确的是（ ）。A． C语言中既有逻辑类型也有集合类型 B． C语言中

冬至日(12月22日)凌晨4点(地方时)一架飞机从甲地 (60ºN、100ºW)起飞，沿最近航线匀速飞行，8小时后抵达乙地 (60º N、80ºE)。回答10－12题。

飞机出发时的航线 　　　　　　　　　　　　

A．朝北　

B．朝南　　

C．朝西北　　

D．朝东北

盘角时，砖层上口高度一般比皮数杆标定的皮数低( )。

A．1～5mm

B．5mm

C．5～10mm

D．10～15mm

将一定量铝粉和氧化铜混合加热，反应的化学方程式为：

3CuO+2Al  3Cu+ Al₂O₃。反应结束后，为了检验氧化铜是否完全反应，取少量反应后的固体，加入足量稀硫酸，充分反应后，将铁片插入溶液中。下列叙述的现象中，能说明氧化铜没有完全反应的是

A．加入稀硫酸后，有气泡生成

B．加入稀硫酸后，没有气泡生成

C．加入稀硫酸后，溶液中有红色不溶物质

D．插入溶液中的铁片表面有红色物质出现

The heat generated by the operating system war between rivals IBM Corp. and Microsoft Corp. is (21) .
Windows 95 and OS/2 introduce a new (22) . Both systems claim to multitask legacy DOS and 16-bit Windows applications. However, only OS/2 can provide full memory (crash) protection for these legacy applications because it is capable of running each DOS and Windows application within its full-protected memory address space.
Windows 95 will run all current Windows applications in the same shared- memory address space, affording full memory protection only to the (23) 32-bit Windows 95 applications. In other word, Windows 95 users will have to (24) their current Windows applications to Windows 95 version to match the memory protection OS/2 now delivers.
While OS/2 does afford superior memory protection and multitasking for legacy DOS and Windows applications, it will not be able to run any Windows 95 applications. IBM may address this (25) in an update of the OS but has no present plans to do so.

A. old B. big C. new D. original

玻璃板液面计时依据（）原理工作的。

A.连通器

B.压力传递

C.流体压差

D.流体能量方程