Астрономия :
луна при движении вокруг земли может находится от неё на расстоянии 405696 км и 363104 км. на каком расстоянии от земли луна находится в перигее?

Junk food has for a long time been eaten by people.  It is considered easy to get and cheap to buy.  Lots of commerciasl every day are broadcast  on the radio and TV. 
I strongly believe that advertizing junk  and unhealthy food should be prohibited.  Doctors say that junk food leads to obesity and serious diseases.  Children like it because it looks nice and smells nice.  But they are not aware of the danger. 
Some people may think that such a ban on junk food advertisement is a  violation of rights.  It also poses danger to freedom of speech and mass media, they may think. 
But I consider that our nation's health is more important.  So we must do all we can to teach people to choose healthy food for themselves and their children. Results of scientific research in this field should be made public.  So the people will  finally make the right choice!

1. Unless your friend has an invitation, he will not be able to go to the party.

2. She will late for the lesson if she doesn't leave earlier.

3. If you are angry, they will not let you in the house.

4. He will not open the book unless he knows what tasks to do.

5. We shall have to stay home if the weather gets worse.

6. Unless you are more careful with the knife, you will cut yourself.

7. If I tell you a secret, will you promise to keep it?

8. If my mother does not have to work next weekend, we will be able to go to the funfair.

Объяснение:

Схема построения условных предложений типа First Conditional:

           [If + Present Simple], + [Future Simple]    

либо   [Future Simple]  +  [If + Present Simple]

В условной части (где "если") глагол в Настоящем Простом времени, в результативной части - глагол в Будущем Простом.