Предмет: Геометрия, автор: Амелия15

49+25 баллов! Помогите, пожалуйста, с геометрией! Диагональ цилиндра, осевое сечение которого является квадратом, равна диаметру шара. Найдите отношение объемов шара и цилиндра

Амелия15: Чертежей нет. Вы можете это решить?

Амелия15: Какую-нибудь.

Ответы

Автор ответа: Simba2017

пусть радиус шара а
Тогда диагональ 2а
В цилиндре высота и диаметр равны 2a/√2=a√2
Радиус цилиндра a/√2
V (цил)=pi*(a/√2)^2)*a√2=pi*a^3/(2√2)
V(ш)=4pi*a^3/3
V(ш)/V(ц)=8√2/3

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Read the text and do the tasks after it.

People nowadays are more health-conscious than they used to be. They understand that good health is above wealth.

To be healthy we should avoid different bad habits that can affect our health. In my opinion, smoking and drinking too much alcohol are the worst ones. It's common knowledge that smoking and drinking can shorten our lives dramatically. Smoking, for example, causes a number of heart and lung diseases, such as pneumonia, emphysema and cancer. Besides, it makes your teeth yellow and skin unhealthy. Fortunately, in recent years smoking has received a lot of bad publicity, and fewer people smoke nowadays. Some companies don't employ people who are smokers. Smoking has been banned in most public places because everyone agrees it does harm to our health.

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1) (Points: 1)

The text is about .

А) lung diseases
Б) diets
В) healthy lifestyle
Г) vegetarians

2) (Points: 1)

Choose the right sentence.

А) People don’t think about their health nowadays.
Б) Overeating can lead to obesity.
В) Smoking has no effect on your body.
Г) People can’t count the number of calories.

3) (Points: 1)

Find the wrong statement.

А) Some people consider meat to be harmful.
Б) More people prefer not to smoke.
В) No one enjoys pizzas and hamburgers.
Г) Skipping meals seems to be less dangerous than drinking alcohol.

4) (Points: 1)

Complete the sentence (according to the text).

What is tasty is not always _________________________________.

А) dangerous
Б) low fat
В) unhealthy
Г) healthy

5) (Points: 1)

Answer the question.

What (according to the text) can help people to keep fit?

А) Going in for sports.
Б) Sleeping 4 hours a day.
В) Spending as little time in the open air as possible.
Г) Getting up late.

6) (Points: 1)

Choose the best title for the text.

А) How to lose weight?
Б) What is good and what is bad for our health
В) Several tips how to give up smoking
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(Points: 6)

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