银行保险可以有效提高保险公司的业务规模，进而降低交易成本，获得（ ）效应。
A．规模经济
B．范围经济
C．协同经济
D．技术经济
参考答案：A
用所给单词的正确形式填空。
1. He ___________ (visit) the Great Wall last year.
2. We ___________ (have) a good time yesterday.
3. We often ___________ (go) to school by bus last year.
4. I ___________ (live) in the village when I was a child.
5. Mike ___________ (see) a big tiger in the nature park last year.
6. Sam ___________ (do) the housework yesterday.
根据《固定电话交换设备安装工程验收规范》，程控交换机试运转验收，应从初验后不少于（）个月。
A.1
B.2
C.3
D.4
