Вопрос школьника по предмету Математика
Россия – страна с самой большой территорией, ее площадь оценивается в 17,1 млн. км2
.
Чему равна масса графена такой же площади? Если весь этот графен получен из графитового
куба, чему равна сторона куба?
ПОМОГИТЕ ПОЖАЛУЙСТА (ДАЮ 20 БАЛОВ)
Ответ учителя по предмету Математика
Графен представляет собой плоскость графита толщиной в 1 атом углерода или 1 нм (нанометр).
Массу вещества описывает формула m = V*p, где V — объём, а p — плотность вещества, в данном случае 0,77 мг/м3
Объём параллелепипеда описывает формула V=H*W*L, где H — высота, W — ширина, L — длина. Получаем 17,1*(10 в 11 степени)*(10 в -9 степени)=17100 метров кубических
Сторона куба графита будет равняться корню 3-й степени из 17100
Масса 17100*0,77=13167 миллиграмм
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6класс
Chapter 3
The Cat in Boots continued for two or three months to bring presents to the King. Every time he came to the palace and said, «Your Majesty, here’s another present from my master, the Marquis of Carabas.»
Then one day one of the Cat’s friends in the palace said to him, «The King wants to drive today in his carriage along the bank of the river. His Majesty is going to take his daughter with him.»
The young princess was a very beautiful girl.
The Cat in Boots said to his master:
«Now you must do what I tell you.»
The miller’s son knew nothing about the Cat’s new plan. But he was sad and unhappy. That’s why he agreed at once.
«Be it so,» he said. «Tell me about your plan.»
«I don’t ask much,» said the Cat, looking wise, as cats can. «All you must do is to go and bathe in the river. I know a good place. Then leave the rest to me. Only remember that you are no longer yourself, but the Marquis of Carabas.»
«OK,» said the miller’s son, «it’s all the same to me.»
He went to the bank of the river, took off his clothes and went bathing. The Cat followed his master and hid his clothes under a great stone.
At that moment the King drove past that place in his carriage. The Cat began to shout at the top of his voice:
«Help! Help! The Marquis of Carabas is drowning!»
The King heard the shouts and put his head out of the carriage. He recognized the Cat.
«Guards!» he said. «Help the Marquis of Carabas! Quick!»
The guards ran to the river. They quickly pulled the young man out of the water.
The Cat came up to the King’s carriage. He made a low bow and gave his explanations.
«My master went bathing,» he said, «and suddenly some thieves came. They took all his clothes and ran away. And now the Marquis of Carabas can’t appear before Your Majesty and your beautiful daughter.»
«Oh, it’s not a problem at all,» said the King.
He ordered one of his guards to ride back to the palace and bring fine clothes for the Marquis of Carabas.
Soon the guard brought a nice suit for the miller’s son. The young man put it on and came up to the carriage to thank his majesty.
The miller’s son wasn’t rich, but he was a handsome and well-built fellow. In the King’s elegant suit he looked like a real gentleman.
The beautiful princess admired the handsome young man very much. The miller’s son looked at the girl several times, and she fell in love with him.
The King was very happy to meet the Marquis of Carabas. He asked the young gentleman to sit with him and his daughter in the carriage. Of course, the miller’s son didn’t refuse.
Exercises
1. Answer the questions.
1) How long did the Cat continue to bring presents to the King?
2) What did he hear one day in the palace?
3) What did the Cat ask his master to do?
4) What kind of explanation did the Cat give to the King?
5) Where did the King send his guard?
6) Why did the princess fall in love with the miller’s son?
2. Complete the sentences.
1) Every time the Cat brought presents to the King and said …
2) The Cat hid his master’s clothes …
3) The miller’s son looked like a … in an elegant suit.
3. Say why:
1) the miller’s son agreed to go bathing.
2) the King stopped by the river.
3) the miller’s son didn’t refuse to sit in the King’s carriage.
4. Fill in the nouns from the text.
1) The King drove along the ___ of the river.
2) The miller’s knew nothing about the Cat’s new ___.
3) The ___ brought a nice suit from the palace.
4) The young ___ fell in love with the miller’s son.
5. Put the verbs in brackets in the right form.
1) «Help my master!» (to shout) the Cat.
2) The guards (to pull) the young man out of the water.
3) The miller’s son (to come up) to the window of the carriage.
4) «The thieves (to take away) my master’s clothes,» said the Cat.
6. Fill in the prepositions from the box.
in under at for
1) The King received gifts from the Marquis of Carabas ___ a long time.
2) «Guards!» shouted the King ___ the top of his voice.
3) The Cat didn’t hide his master’s boots ___ the tree.
4) The miller’s son fell ___ love with the princess.