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【简答题】
拿来一片黄色的金属向同学们炫耀说他捡到了黄金．小宝说他曾在网上看到过，有一种铜锌合金外观和黄金相似，常被误认为是黄金．于是他与开始探究． 【提出问题】这块黄色的金属是黄金?还是铜锌合金? 【猜 想】①认为是黄金； 【查阅资料】合金中的金属保持各自的化学性质，高温下不与氧气反应，锌在高温下与氧气反应生成白色固体． 【设计实验】①设计的实验是：截取一小片黄色的金属放在石棉网上用酒精灯加热； 【现象与结论】①在实验中观察到黄色的金属变黑，则他的猜想_____________．黑色物质是____________________．写出反应的化学方程式_______________________________________．
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【单选题】— How can we get to the airport ? It’s too far and expensive to take a taxi. —Don’t worry.There is a bus service to the airport.
A.
.regular
B.
general
C.
.normal
D.
usual
【单选题】Which one is not proper for a formal pick-up service at the airport?
A.
You may prepare a placard .
B.
Check the flight No. in advance.
C.
You may wear as usual.
D.
Arrive at the airport early.
【单选题】－How can we get to the airport? It’s too far and too expensive to take a taxi. －Don’t worry. There is a ________bus service to the airport.
A.
regular
B.
general
C.
normal
D.
Usual
【单选题】Which of the following is true?
A.
The international service in August would be as much as in July.
B.
The flow of international passengers will be more than that in July.
C.
The airport will provide less service than in July.
D.
The flow of international passengers will be more than that in usual time.
【简答题】络筒的目的和要求是什么？
【简答题】My last overseas business trip was highly enjoyable. I set off fairly early in the morning, so there was hardly any traffic on the (1) ___________, and I got to the airport very quickly. I drove strai...
【单选题】Why will the crew not be flying back home via Kazakhstan's Karaganda airport as usual?
A.
Because the airport has been shut down.
B.
Because the airport is used to launch missions.
C.
Because the airport is too far.
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