Что такое энергетический обмен?

Hi! How are you?
 - Hi, I'm fine, thank you, and you?
 - I'm OK. you know, tomorrow there will be three concerts. Let's go to one of  them? 
- Oh, it would be great! And what are the concerts?
 - one is of a modern pop singer, the other is of classical music and the third one is rock music.
- And how much are the tickets?
- A ticket to the pop singer concert costs 60  pounds. A ticket to the classical concert  costs 30 pounds . A ticket to the rock concert  is 50 pounds. 
-  I'd like to go to the rock concert and I have 50 pounds. And you? 
- I also have 50 pounds. But why - rock music?
- It is great! and it cheers me up. It makes me energetic. And I like loud rhythmic music. What about you? where would you like to go?
 - as for me I'd go to all the three concerts. But I don't have enough money to do that. 
- oh, I see So?
- So, we go to  the rock concert!
 - Yes! When does the concert start? Late in the evening?
 - No, it begins at 6pm.
- excellent!
- Let's meet tomorrow in the concert hall? 
- Yeah! See you!
- see you!