已知定义在R上的函数$f\left(x\right),g\left(x\right)$满足$\frac{f\left(x\right)}{g\left(x\right)}=a^x$，且$f^{\text{'}}\left(x\right)g\left(x\right)<f\left(x\right)g^{\text{'}}\left(x\right)$ $\frac{f\left(1\right)}{g\left(1\right)}+\frac{f\left(-1\right)}{g\left(-1\right)}=\frac{5}{2}$，若有穷数列$\left\{\frac{f\left(n\right)}{g\left(n\right)}\right\}$（$n\in N^{*}$）的前n项和等于$\frac{31}{32}$，则n等于（   ）

考察中国人口发展的历史，我们发现明代中后期中国人口数量出现了快速的增长。人口的快速增长得益于精耕细作生产方式的推广和高产作物的引进。明清时期人口的快速增长，最深远的历史影响是（  ）

    Long ago I came to the city near my hometown to find a job. I met all kinds of 1 and so I used up all my money soon.

    One day, I 2 a bus quietly at dusk when most people got off work. Suddenly, a 3 cried loudly, “Someone has 4my money!” I felt 5, because his money was in my 6 Some people suggested the bus be 7 to the police station, but some were against it 8 they were in a hurry to go back home. The whole bus was very 9. The driver then 10the bus by the road and turned on the lights to 11 the money. At that time, one passenger said, “Turn off the lights and give the thief a chance to take out the money.” Then the bus got 12When I was still struggling (斗争) in mind whether to take out the money or not, the lights were on again. There was no 13 on the floor. Someone said again, “Give him one more 14” Then the lights were off again. My heart kept beating fast. The lights were on again but they got the 15result. The passengers were in heated discussion again. At that time, someone said again, “Give him the 16 chance!” Suddenly I felt 17and took out all the money when the lights were off again.

    For many years I have felt 18 to the one who gave me three chances to  19 my mistake. When the first and second chances come, you may not be prepared well or don't have enough 20 to act. When the third chance comes you should know clearly what you should do.