gmat 菜鸟请教大虾们两道题

一个是逻辑题：
one analyst predicts that Hong Kong can retain its capitalist ways after it becomes part of China in 1997 as long as a capitalist Hong Kong will be useful to China;that a capitalist Hong Kong is prosperous; and that Hong Kong will remain prosperouus as long as it retains its capitalist ways.
If the predictions above are correct, which of the follwing further predictions can logically be derived from them?
答案给的是：
B) If HK retains its capitalist ways until 1997,it will be allowed to do so afterward.
但是我不明白为什么不是
D)HK will be prosperous after 1997.
我自己分析此题如下：
题目给出三个论据
1。只要资本主义制度下的香港对中国是有益的，那97以后就继续资本主义
2。资本主义制度下的香港繁荣
3。只要继续资本主义，香港会继续繁荣
那么如果选B，就是由2、3推论出1
那么为何不由1、2，推论出3，那就是D选项了阿？~

菜鸟钻牛角尖中，希望各位大虾帮忙~

第二个问题是数学题：
The projected school tax rate is set at $11.25 per $1000.What is Mr X's house assessed for?
(1) Mr X will pay $202.25 in school taxes under the proposed new budget
(2) He paid @217.85 last year.
答案是选A，解释是用202.25/0.01125，
但是我不明白他交学校的税和他房子有什么关系？？？