Find words/phrases in the dialogue in Ex. 4a which mean: 1 What's the matter? 2 I will do my best. 3 What exactly is the problem? 4 Any time.

1 What's up? What is it?(В чём дело?)
2 I'll try,(Я буду стараться).
3 What exactly happens?(В чём именно проблема?)
4 You're welcome.(В любое время).