为了提高测向精度和方位分辨力,应选用水平尺寸大的天线反射体。

题型:判断题

问题:

为了提高测向精度和方位分辨力,应选用水平尺寸大的天线反射体。

考点:电子与通信技术雷达工程雷达工程题库
题型:判断题

下列离子方程式书写正确的是( )

A.在蓝色的淀粉溶液中通入足量SO2后成无色溶液:I2+SO2+2H2O=2I-+SO32-+4H+

B.等物质的量的亚硫酸氢铵与氢氧化钠溶液混合:NH4++HSO3-+2OH-=SO32-+NH3↑+2H2O

C.碳酸氢镁溶液中加入过量石灰水:Mg2++2HCO+Ca2++2OH-=CaCO3↓+2H2O+MgCO3

D.碳酸氢钠溶液中加入过量氢氧化钡溶液:HCO+Ba2++OH-=BaCO3↓+H2O

题型:判断题

图1-16所示4种材料的应力—应变曲线中,塑性最好的是材料()。

A.A

B.B

C.C

D.D

题型:判断题

选做题:阅读下面短文,并根据短文后的要求答题请注意问题后的词数要求。

     Called "The School of the Future" and created with help from software giant Microsoft, a recently-

opened public school in Philadelphia, US, is believed to be the first in the world to combine innovation

teaching methods with the latest technology. At this school, students work on wireless laptops, teachers

eschew traditional subjects for real-world topics and parents can track their children‘s work on the Internet.

     The school, which costs the school district $63 million to build, is free and has no entrance exams.

The 170 ninth-grade students were selected at random from l,500 applicants.

     Philadelphia School District Chief Executive Paul Vallas told students they would be observed by other

schools around the world. "You have become instant role models," Vallas said. "People are going to be

watching you."

     Students still sit in classrooms, but lessons rely heavily on information found on the Internet and on

interactive software. Students will be allowed to learn at their own pace. Homework is done on the computer

and sent to the teacher for grading and parents can access to the school‘s network to read the teacher’s

feedback on their children’s progress.

     Traditional education fails to teach students the skills of problem-solving, critical thinking and effective

communication, which they need to succeed in the 21st century, Principal Shirley Grover said in an interview.

"It‘s not about memorizing certain algebraic equations (代数方程式) and then presenting them in 8 test,"

Grover said. "It’s about thinking how maths might be used to solve a quality of water problem or how it

might be used to determine whether or not we are safe in Philadelphia from the bird flu."

     David Terry, 14, said he was hoping to "turn over a new leaf" after discipline problems in his previous

school left him with an "average to really bad" academic record. "This is a great opportunity for me," he said.

"In other schools, I would not _____."

1. What‘s the best title of this passage? (Please answer within 10 words.)

    ______________________________________________________________________________________

2. Which sentence in the passage can be replaced by the following one? Although the students have their

    lessons in classrooms, they mainly learn through the Internet and on some software.

    ______________________________________________________________________________________

3. Please fill in the blank in the last paragraph with proper words or phrases to complete the sentence. (Please

    answer within 10 words.)

    ______________________________________________________________________________________

4. Do you think this kind of school good? Why? (Please answer within 30 words.)

    ______________________________________________________________________________________

5. Please translate the underlined sentence in the fifth paragraph into Chinese.

    ______________________________________________________________________________________

题型:判断题

人体排出体内代谢废物的过程叫排泄.下列各项中,不属于排泄的是(  )

A.通过肛门以粪便形式排出食物残渣

B.通过呼吸系统以气体形式排出二氧化碳和少量水

C.通过皮肤以汗液形式排出部分水、少量无机盐和尿素

D.通过泌尿系统以尿液形式排出大部分水、尿素和无机盐

题型:判断题

一般的浏览器用不同的颜色来区别访问过和末访问过的连接。

更多题库