工作票应由工作票签发人签发。
参考答案：对
With the electricity __________, people use candles instead.[ ]
A. cut off
B. cut in
C. cut away
D. cut down
Oracle10G，数据库缺省的优化器类型为（）。
A.All_ROWS
B.Cost-basedoptimizer
C.Rule-based optimizer
D.Choose
