Verified answer

1 Yes, I have. I have been to St Petersburg. (или No, I haven't been to St Petersburg.)

2 Yes. I have translated a few texts from English into Russian.

3 Yes, I have. I've read "White Fang" («Белый Клык»).

4 No, I haven't. I have never been to the Bolshoi Theatre.

5 No, I haven't. I haven't seen any.

6 Yes, I have. (или No, I haven't - если вы не летали самолетом)

7 Yes, I have. I have received letters from my friend who lives in France.

 или No, I haven't. I haven't received any letters from foreign countries.

8 Yes, it has. It has stopped raining.

9 Yes, he has.