产褥期(puerperium)
参考答案：
从胎盘娩出至产妇全身各器官除乳腺外恢复或接近正常未孕状态所需的一段时间，称产褥期。
A．A、B两点场强相等
B．A、B两点电势相等
C．负电荷从A运动到B，电场力先增大后减小
D．正电荷从A运动到B，电势能先增大后减小
In the foreign trade business, the payment is always made by L/C. In this sentence, L/C is the abbreviation for （）.
A. Bill of Lading
B. Commercial Invoice
C. Buying Contract
D. Letter of Credit
