I have to take part in a competition. You have to choose 3 - 4 pieces of Grade 8.
However, I don't know the standard of the pieces of my choice.

Please help me to find out the standard of them and give me advice:

1.Tchaikovsky: June from Seasons
2.Mozart: Sonata in C KV 309 rondo
3.Chopin : Etudes Op.10 No.1
P.S. Sorry for my bad English.