下列特点中,所谓“合金”必须具有的是
(1)具有金属特性 (2)通过熔合加工 (3)有两种或两种以上金属(或金属与非金属) (4)铸造性很好
A.(1)(2)(3)
B.(1)(3)(4)
C.(2)(4)
D.(1)(4)
答案:A
合金的定义:有两种或两种以上金属(或金属与非金属),通过熔合加工,具有金属特性的物质,所以,“合金”必须具有的是(1)(2)(3),故选A。
下列特点中,所谓“合金”必须具有的是
(1)具有金属特性 (2)通过熔合加工 (3)有两种或两种以上金属(或金属与非金属) (4)铸造性很好
A.(1)(2)(3)
B.(1)(3)(4)
C.(2)(4)
D.(1)(4)
答案:A
合金的定义:有两种或两种以上金属(或金属与非金属),通过熔合加工,具有金属特性的物质,所以,“合金”必须具有的是(1)(2)(3),故选A。
阅读理解。 | ||
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1. Who did a lot of work for the exams? | ||
A. Sara. B. Steve. C. Both. | ||
2. Sara enjoys _________. | ||
A. playing computer games B. doing scientific experiments C. learning English | ||
3. The teacher thinks Steve needs to _________. | ||
A. improve his math B. learn English better C. play more computer games | ||
4. In the teacher's opinion, Steve should be _________. | ||
A. a scientist B. an English teacher C. a computer programmer | ||
5. Which of the following activities is the most suitable to improve Sara? | ||
A. Playing computer games. B. Watching TV. C. Playing basketball. |