在89、121、132、480、157、783中，是3的倍数的有______．

为什么实际橡胶弹性中带粘性，高聚物粘性熔体又带弹性？列举它们的具体表现形式。如何减少橡胶的粘性？在挤出成型中如何减小成型制品中的弹性成分？

试述捕食作用对种群数量和质量的调节作用。

阅读理解。

     Do you wake up in the morning dreading the moment that your feet have to hit the floor for you to get

ready for work? If that's the case, join most of Americans. Very few people wake up to that an noying alarm

clock and spring out of bed excited about having to go to work.

     As if that were not enough, most of us have to fight traffic get- ting there, usually an hour's drive. Then,

when we get to work, we have to fight with unruly co-workers or a nagging boss. And to make matters worse, you have to fight the same traffic going in the oppo site direction just to get back home.

     Making dinner, fixing plates, eating and then straightening up afterwards is a job within itself. If that sounds

like your life, you probably have a J-O-B. You know what J-O-B stands for? Just Over Broke, that's what!

With a job, most Americans are living pay- check-to-paycheck and hating every minute of it. I know because

I was doing the same thing: trading time for money. And, I came to a conclusion that it stinks (糟糕透了)! Big

time!

     Looking around at my co-workers, friends and relatives, I saw that they were all doing the same thing I

was doing. They were com plaining about the same things I was complaining about: not having enough time

or money. And, I decided that I wanted to do something different.

     So, I started a home-based business. There are several to choose from. The extra income has done so

much for our family. We can vacation more. We have been able to give more. And, we've e ven been able to

do something calling save! It's been amazing.

     Therefore, if you're sick and tired of being sick and tired, it's time you make a change, too. The definition

 of insanity (疯狂) is doing the same thing over and over and expecting different results. I know you aren't

stupid. If you continue to do what everyone else is doing: trading time for money, you're going to keep getting

what eve ryone else is getting: being broke and not having the time to do what is really important to you.

     Do your due diligence? Find a home-based business that works well for you. Go to work, and live the life

you've always imag ined!

1. According to Paragraph 1,which of the following statements is TRUE about most Americans?

A. Most Americans are excited to go to work every day.

B. Most Americans are used to sleeping in the morning.

C. Most Americans are tired of having to go to work every morn ing.

D. Most Americans have alarm clocks to wake them up in the morning.

2. By writing the first three paragraphs, what feeling does the writer express?

A. Regret.

B. Joy.

C. Pride.

D. Dissatisfaction.

3. What does" something different"in Paragraph 4 refer to?

A. To set up a business at home.

B. To complain about life and work.

C. To spend more time on holidays.

D. To resign from the former job and get a new one.

凡是后牙锻造金属全冠龈边缘的最佳选择是（）

A.龈上凹形边缘

B.龈下肩台边缘

C.龈上肩台边缘

D.龈下凹形边缘

E.平龈边缘