题目

有这样一个问题:探究函数 的图象与性质.小东根据学习函数的经验，对函数 的图象与性质进行了探究. 下面是小东的探究过程，请补充完整: （1） 函数 的自变量x的取值范围是; （2） 下表是y与x的几组对应值. x … -3 -2 -1 12345… y… 3m… 求m的值; （3） 如下图，在平面直角坐标系xOy中，描出了以上表中各对对应值为坐标的点.根据描出的点，画出该函数的图象; （4） 结合函数的图象，写出该函数的一条性The weather is getting hotter. You are thirsty playing basketball or riding home from school. A cold drink may be just the thing. But be careful what you are drinking. Something that looks cool may not be good for your health. There are plenty of “energy drinks” on the market. Most of them have beautiful colors and cool names. The lists on them tell you they are helpful to your health. Sounds great!But after a careful check you may find that most energy drinks have lots of caffeine(咖啡碱)in them. These drinks are especially aimed at young people, students, busy people and sports players. Makers sometimes say their drinks make you better at sports and can keep you awake. But be careful not to drink too much. Caffeine makes your heart beat fast. Because of this, the International Olympic Committee(IOC) has limited(限制) its use. Caffeine in most energy drinks is at least as strong as that in a cup of coffee or tea. Possible health dangers have something to do with energy drinks. Just one box of energy drink can make you nervous, have difficulty sleeping and can even cause heart problems. Scientists say that teenagers should be discouraged from taking drinks with a lot of caffeine in them.1.Many people like drinking energy drinks because of the following EXCEPT that ______.A. they have beautiful colors and cool namesB. they can keep them awake and better at sportsC. they have lots of caffeine D. they are said to be helpful to health2.The underlined word “discouraged” can be replaced(替换) with ______.A. encouraged B. dislikedC. helped D. stopped3.Which of the following can be the best title of the passage? ______A. What’s the Use of Energy Drinks?B. What’s That in Energy Drinks?C. Who Can Drink Energy Drinks?D. Why Can’t We Buy Energy Drinks?