Докажите что для любой геометрической прогрессии {bn} верно равенство b9+b10 / b7+b8 = b11+b12 / b9+b10

Добрый день. Помогите пожалуйста.

Change the direct speech into the reported speech.

1.                 – Is ink expensive, Dad?

- No, it isn’t. What makes you think so?

- Mother seems quite disturbed because I spilt some on the carpet.

Susan asked her father… . Susan’s father told her… . Then the girl said … .

2.                 – Mummy, why is it cold today?

- It is winter now. It’s always cold in winter

- But why is it always cold in winter?

- Oh, Susan, I didn’t ask my mother so many questions.

- Now I understand why you can’t answer my questions!

Susan asked her mother… . Her mother answered… . Susan repeated the question … .

Susan’s mother got angry and exclaimed … . Susan came to the conclusion