Докажите, что боковые грани правильной пирамиды равнонаклонены к плоскости её основания.

1. It's easier to meet  friends in the city, because there are many people in the city - so you can easily meet a lot of people.
2. I think it's the mall, because it has a cinema, a bowling and lots of cafes.
3. Of course in the mall, 'cause it is big and has lots of shops.
4. Quiet hard question, but I think it is school, because our school staff always clean it well.