下列何项检查为不必要
A．宫颈分泌物细菌培养及宫颈涂片革兰染色检查B．诊断性刮宫C．白细胞分类计数D． * * 后穹窿穿刺E．B超检查
参考答案：B
人工圣诞树
Given the following inventory data about a firm: Beginning inventory 20 units at $ 50/unit Purchased 10 units at $45/unit Purchased 35 units at $ 55/unit Purchased 20 units at $ 65/unit Sold 60 units at $ 80/unit What is the inventory value at the end of the period using FIFO（）
A. $3100.
B. $3475.
C. $1575.
