— (可能)he is in the library,but I'm not sure.

①形成峡谷 ②地表隆起 ③形成高大山脉 ④形成新的海洋
①每个人的生命都是独一无二的,都有自己独特的风格和特点 ②要珍爱自己的生命和别人的生命
③地球上的生命是人类社会长期发展的产物 ④要热爱大自然这个生命的家园,保护环境,维护生态平衡
—他是迈克·米勒。
—is name?
—He is Mike Miller.
中,
,过A作
于点D,点E为直线
上一动点,把线段
绕点E顺时针旋转
,得到线段
,连接
、
,直线
与
相交于点G.
时,填空: ①
的值为;
②
的度数为;
时,请写出
的值及
的度数,并就图2的情形给出证明;
时,若
,请直接写出
的面积.
|
小明 |
小华 |
小芳 |
|
|
笔记本(本) |
15 |
24 |
27 |
|
钢笔(支) |
25 |
40 |
45 |
|
总价(元) |
330 |
528 |
585 |

"Please take my penny," said Maggie to old Dan, the fisherman, who sat on a bench repairing his nets.
Her brother Andrew drew her back, whispering, "Maggie, he is not a beggar (乞丐)!"
But Maggie paid no attention. "Please take it," she said again. Old Dan smiled, and took it. "Thank you, little miss," he said, "It is kindly meant."
After that, Maggie went to the beach to gather shells. She never thought how fast the hours were passing until being tired. She sat down on a rock. Soon she was scared because the sea water was going up. She wanted to go home, but she found the places she had gone down easily very difficult to climb up. The stones were wet and smooth. What could poor Maggie do? She felt sad and cried.
Luckily, Dan's large dog Rover jumped down from a rock! Rover raised his loud bark. The fisherman had taken his nets to the top of the cliffs (悬崖), and was laying them out in the sun when he heard the loud barking of a dog. He felt sure that it was Rover, and Rover was in trouble, so he looked over. There he saw it all.
"Bless her! It is the little one that was so kind-spoken to me this morning!" he cried, and he hurried to his sons' rooms.
"Quick, boys, quick!" he said. "Get to the boat, and row fast to the sea. There is a poor child there just waiting to be helped." The fishermen lost no time, and soon little Maggie and Rover were rowed safely to land! Old Dan was waiting there to lift her out to give her into her mother's arms.
"It was the penny that did it, madam," he said to Mrs. Weston later. "I saw Rover looking at her when she put the penny. And I am thinking he had been looking after her all the day."
Some years later, Rover came to Maggie's home with a little note, in which was written—"Will Maggie help Rover?—his master is dead."
(提出问题)生石灰样品的成分是什么?
(作出猜想)生石灰样品的成分可能是CaO、Ca(OH)2和CaCO3中的一种或几种。
|
实验 |
实验操作 |
实验现象 |
实验结论 |
|
① |
取样品于烧杯中,加水溶解,用手触摸烧杯壁。 |
烧杯壁发热 |
|
|
② |
将①中液体过滤,取少量滤液于试管中,向其中滴入。 |
溶液变红 |
有Ca(OH)2 |
|
③ |
取②中的少许滤渣于试管中,向其中滴加少量稀盐酸。 |
|
无CaCO3 |
同学们经过讨论,发现通过实验②不能得出样品中一定含有Ca(OH)2 , 理由是 _。
①生石灰要保存。
②设计和分析实验时,要充分考虑反应物的量和生成物等因素对实验结论的干扰。
③要确定样品中是否含有氢氧化钙,还需要学习更多化学知识才能解决。