关于酶的叙述，错误的是（　　）

小明同学解答如下：

∵a=1   b=2 $\sqrt{3}$    c=2 

∴b²﹣4ac=（2 $\sqrt{3}$ ）²﹣4×1×2=4＞0

∴x= $\frac{-2\sqrt{3}\pm \sqrt{4}}{2\times 1}$ =﹣ $\sqrt{3}$ +1

∴x=﹣ $\sqrt{3}$ +1     x=﹣ $\sqrt{3}$ ﹣1

请你分析以上解答是否有错？若有，找出错误地方，并写出正确解答过程．

阅读理解

    I am a karate(空手道) player. I still remember my first karate competition. Like other players,

I was very excited about my event. I watched every player's skills so that I could carefully avoid their moves.

    Somehow, I got into the semifinals(半决赛). In the semifinals, I fell down and hurt myself. I still didn't give up, so I fought back and got into finals. After all, getting the gold medal was my dream.

    In the final competition, there were no supporters on my side, as I was a new face. Instead, the crowd was cheering for my opponent(对手). I could hear only my opponent's name.

    I didn't mind the crowd's cheering. I kept one thing in mind: focus, wait and attack. I had confidence in myself, and I knew that no matter how strong my opponent was, I had to give it my best shot and fight well.

    When the time was up, I was leading with a 3—0 score. One thing I learned from that event is, no matter how strong your opponent is, don't think you are weak or strong. Just give your best shot, and you will make your way to success.

    Win or lose, you will gain important experiences. Learn from every step you take.

我国改革开放之初,各个地区和企业开始关注自行车、缝纫机、手表等的生产经营,后来重视电视、冰箱和洗衣机等的生产经营,现在看重的是汽车、电脑、环保设备等的生产经营。这种生产经营的变化是由于（  ）