题干

如图甲为适宜温度条件下绿藻光合速率与光照强度的关系,图乙为25℃条件下,将绿藻置于密闭玻璃容器中,每2h测一次CO2浓度变化情况(假设细胞呼吸强度恒定).下列叙述中,错误的是(  )

A:图甲中光照强度相对值大于7时,限制光合作用的主要环境因素是CO2浓度

B:图甲实验能确定叶绿体产生O2的最大速率相对值,其最大速率为8

C:图乙所示实验中在2〜4h间可能没有光照,实验经过12小时后绿藻干重基本不变

D:图乙实验过程中4〜6h平均光照强度小于8〜10h平均光照强度

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B

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    You have probably heard the saying,"When life gives you lemons,make lemonade."Since lemons are considered bitter and lemonade is considered sweet,the saying tells you to make the best out of a bad situation.

    Unfortunately,when something bad happens,it's not uncommon for most people to talk about it to anyone who'll listen,and complain about life,"Why me?"That's like getting a bag of lemons,putting them down,and thinking, "Lemons taste bad!I'd rather have chocolate!"If you don't make anything with the lemons,they will go bad.But what if you did something with them?What if you made lemonade?Isn't it possible to do something similar with a bad situation?

    Here's an example.Let's say you're about to go to the movies,but you discover you have a flat tire(瘪胎).You consider this a terrible thing. After all,you are really looking forward to spending some time with Ryan Gosling and Emma Stone.Now you're all stressed out,hating the tire,the car,and your life.But what if you called AAA,got your tire fixed or got caught up on things that you'd been meaning to do?What if you did some reading,or had coffee with a friend instead?A negative experience can be turned into something positive.Almost anything can work itself out into something better.You can't change what has happened,right?So make the best of it.I'm not saying it will be easy. The easy thing to do is complain about your bad situation and not consider what it could be turned into.

    Next time when some unfortunate things happen,stop and think,"How can I turn this around?How can I make it a positive experience?You needn't fear difficulties.As long as you keep on changing it,you will see the benefits(好处)at last.