за 10 одинаковых тетрадей нужно заплатить на 75 рублей,больше чем за 7 таких же тетрадей.Сколько стоит 5 таких тетрадей?

 пожалуйста!!!1

Составь уравнения реакций калия с водородом и серой. Назови продукты реакций.

Вычисли объем водорода (н.у.), который выделяется при взаимодействии рубидия массой 17г с водой. 

Решите пожалуйста!

Choose the correct pronouns.

1.(Our, us) office manager often meets foreign businessmen and discusses prices for different goods with (their, them).

2. Come and meet (my, me) family at the weekend.

3. We're going to the sport centre. Would you like to go with (our, us)?

4. I want to meet (his, him), but he doesn't want to meet (my, me).

5. -Do you know this man?

-Yes, I work with (his, him).

Use the correct pronouns.

1. I read a lot of English books. I read ... in the evening.

2. Lavrov is speaking to Mr Bell. He is speaking to ... about the contract.

3. Kate is my friend. I meet ... in the office every day.

4. My daughter is reading a book about London now. She is reading ... with pleasure.

5. I often meet my friends. I usually meet ... at weekends.

6. We learn English. Our work helps ... to speak English well.

7. Where are the new catalogues? I want to look through ...

8. I'd like to meet Mr Tompson. I am going to make an appointment with ...  today.

найдите неизвестный член пропорции : 6.5:5.2=х:8