1. Every tiger has paws, every sheep has hooves.
2. Fiona bought one candlestick yesterday.
3. There was one knock at the door.
4. It happened in some small village in the south of France.
5. Have you got any map of Europe?
6. When I was walking home I met some boy who was carrying a basket with one small puppy in it.
7. Even every child knows where the sun rises, and you don't.
8. I must send certain telex.
9. - Where is John? - He has gone to the thetre to listen to some opera.
10 Every detective helps to find criminals.
If you push this button, somebody will come.
If you drive so fast, you will have an accident.
If my father comes, I will phone you.
You won't pass your exam If you don't study.
They will win the match if they score one more goal.
I will help you if you give me some sweets.
If I have time this evening, I will watch TV.
We will be late for school if we don't hurry.
If you look carefully, you will see where it is.
If you eat everything, you will be ill.
Do - это глагол "делать". Настоящее простое время. 1 , 2 лицо
Does - she, he, it(3 лицо) настоящее простое время.
Don't - это "do not"(not - отрицание)
Doesn't - does not. Отрицание. She, he, it. Настоящее простое(present simple)
CosB=BC/AB=8/16=1/2
Ответ: cosB=1/2