“暖足贴”利用铁氧化生锈时会放热的原理从而达到给人局部热敷的作用，具有一贴即热，快速热敷的作用，深受大众的喜爱．图甲是某品牌“暖足贴”的图片．A、B两小组的同学，通过查阅资料发现，其主要成份为：铁粉、_刷题宝

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“暖足贴”利用铁氧化生锈时会放热的原理从而达到给人局部热敷的作用，具有一贴即热，快速热敷的作用，深受大众的喜爱．图甲是某品牌“暖足贴”的图片．A、B两小组的同学，通过查阅资料发现，其主要成份为：铁粉、活性炭、水、食盐等物质．

上一题下一题 0.0难度选择题更新时间:2017-09-04 02:02:26

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定义行列式运算

| \begin{matrix} a_{1} & a_{2} \\ a_{3} & a_{4} \end{matrix} | = a_{1} a_{4} - a_{2} a_{3}

f (x) = | \begin{matrix} \sqrt{3} & sin x \\ 1 & cos x \end{matrix} |

的图像向左平移

n (n > 0)

个单位，所得图像关于

y

轴对称，则

n

的最小值为（）

同类题2

补全对话。

A. Can you come?

B. When is it?

C. That day is also my thirteenth birthday.

D. Do you have a soccer game?

E. And we also have a basketball game on October 25^th.

F. What color does he like?

A: Do you have a volleyball game at your school?

B: Ye, we do.

A: ____

B: It's September 28th.

A: ____

B: Yes, we do. It's October 17th. ____

A: When is your school trip?

B: It's May 20th. ____

A: Oh? That's great.

B: I want to have a birthday party on that day. ____

A: OK, thanks.

同类题3

如图所示，平行于光滑斜面的轻弹簧劲度系数为k，一端固定在倾角为θ的斜面底端，另一端与物块A连接，物块B沿斜面叠放在物块A上但不黏连．物块A、B质量均为m，初始时两物块均静止．现用平行于斜面向上的拉力F拉动物块B，使B做加速度为a的匀加速运动，两物块在开始一段时间内的v﹣t图象如图乙所示（t₁时刻A、B的图线相切，t₂时刻对应A图线的最高点），重力加速度为g，则（）

同类题4

阅读短文，判断下列句子与短文内容是否一致

It was Sunday yesterday. The weather was fine. It was sunny and there were no clouds in the sky. Sandy and Sue got up early in the morning. Now they were in the park. It is a big park and it's so beautiful. They saw many people there. Some boys played football on the grass. Some girls danced under the tree. An old man walked beside the lake. A young woman and her little son looked at the fish in the lake. How happy they are!

同类题5

依次填写关联词，都正确的是______________。

我以为她一定最安全了，______________不做门房，______________不是小孩子，______________生得不好看，______________颈子上还有许多炙疮疤。

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