如图所示的电路中,电源电压是6V,当电路中发生哪种障碍时,电压表的示数是约为6V,且两灯都不亮( )
A.L1短路
B.L1断路
C.L2短路
D.L2断路
答案:B
临时住宿登记信息应在被留宿人抵达留宿单位()小时内录入计算机管理系统并做完数据传输工作,禁止积压、超时录入与传输。
A.8小时
B.12小时
C.24小时
D.36小时
—David, there _______ a dictionary and some books on your desk. Please put them away.
—OK. Mum. I'll do it right away. [ ]
A. is
B. are
C. has
D. have