题干

物态变化在工农业生产和生活中的应用十分广泛,如(1)利用干冰实施人工降雨,(2)冰箱通过致冷剂循环流动达到致冷目的,(3)焊接金属部件,(4)制酒工业利用蒸馏法提高酒精纯度,以上实例中,利用汽化、液化两次物态变化达到目的的是 (    )

A:(1) (3)

B:(1) (4)

C:(2) (3)

D:(2) (4)

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D

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    Teachers love to put students into teams.____ Why? Because they know the responsible team members will come through for a good grade.

If you are teamed up with a student who is lazy, the worst thing you can do is let it get you down.____ and it might create a positive change in your partner!

    Try these tips for working with a slacker(懒虫).

    Be excited and provide a good example. Your slacker may be a good person who has developed bad work habits. You may be able to teach your partner some valuable skills for a successful future.

    Think rewards!____ For instance, you could promise to make cupcakes for the next work meeting and encourage your partner to bring a good snack.

    Make some time to sit with your partner and establish a set of work rules and deadlines. Don't quarrel, though. Make it clear that you would like to establish rules to keep you both on track.____ Keep a record of your rules, your initial meetings, and your work. When it becomes obvious in the records that you're doing all the work, talk with the slacker.____

A. Don't let the anger and pain defeat you.

B. Come up with a great reward for meeting some goal.

C. Instead, take some steps to encourage your partner to work.

D. Unavoidably one or more members will try to do nothing.

E. Start out by giving your partner a clear task with a deadline.

F. Show him/her the evidence and suggest he or she pick up the pace.

G. Think about the future and the fact that you are going to be rewarded.