某商场对顾客实行购物优惠活动，规定一次购物付款总额：

（1）如果不超过200元，则不给予优惠；

（2）如果超过200元但不超过500元，则按标价给予9折优惠；

（3）如果超过500元，其500元内的按第（2）条给予优惠，超过500元的部分给予7折优惠．

某人两次去购物，分别付款168元和423元，假设他一次性购买上述两次同样的商品，则应付款是（　　）

    China is a great country with the largest population in the world. In order to solve the population problem, our government carried out one﹣child policy （政 策）before. When it is carried out for some time, many people not only see its advantages but also disadvantages.

    From 2016, two﹣child policy is put into effect. In my opinion, two﹣child policy is good. First of all, two﹣child policy is the gift for some only child. For some families, maybe the parents are only child and they also can have only child. Besides the loneliness of their child, when their child grows up and they grow older, their child marry an only child girl, the burden（负担）on their child and his wife is too heavy. Their child and his wife have to take care of two couples. Usually, a young couple looking after an old couple is a little difficult. But if their parents have two children, they can share the burden of taking care of their parents. It would be much better. Secondly, two﹣child policy can guarantee （保证） the number of Chinese population.

    All in all, one﹣child policy has been out of date. And two﹣child policy is needed and necessary. It can solve the problems of nowadays （现在）and the future.