Bonjour, hi
Réponse :
2- Sherlock observes a return train ticket stub in the palm of her glove and thinks that she has come to London by train.
3- IDK, sorry, need the text...
4- The name of the Lady is Helen stoner, she had come to see Sherlock to find out how her sister died, she also fears that she will meet the same fate as her sister.
Voila :)
