Помогите пожалуйста ответить на вопросы: 1. What are the colours of

Помогите пожалуйста ответить на вопросы: 1. What are the colours of the Americans flag? Why are there 13 stripes on it? Why are there 50 stars on the flag? What do you people often call the American flag?
2. The eagle became the official national symbol of the USA in 1782, didn't it? What symbol is an olive branch? What symbol is arrows? Where can you see the picture of the eagle with an olive branch and arrows?
3. The capital of the USA is Washington, D. C. , isn't it? What do the letters D. C. stand for? Why do people say "Washington, D. C." when they speak about the US capital?
Желанно полный ответ.