一系统中采用8255A作I/O接口,初始化时CPU访问其08BH端口,将它认定方式0输入,则A口的地址为( )。
A.088H
B.089H
C.08AH
D.08CH
参考答案:A
—Have you ever seen a tiger in the wild?
—Yes. I saw_________when I visited the National Park in Guiyang.[ ]
A. which
B. it
C. one
D. that
某地区新建2台1000MW超临界火力发电机组,以500kV接入电网,每台机组设一组浮动用220V蓄电池,均无端电池,采用单母线接线,两台机组的220V母线之间设联络电器,单体电池的浮充电压为2.23V,均充电压为2.33V,该工程每台机组220V直流负荷如表,电动机的起动电流倍数为2。
若220V蓄电池各阶段的放电电流如下:(1)0~1min:1477.8A(2)1~30min:861.8A(3)30~60min:534.5A(4)60~90min:497.1A(5)90~180min:30.3A蓄电池组29min、30min的容量换算系数分别为0.67、0.66,请问第2阶段蓄电池的计算容量最接近哪个值?()
A.1319.69Ah
B.1305.76Ah
C.1847.56Ah
D.932.12Ah