Scarlet Pimpernel help with homework: Why would Armand not reveal to his sister

1.Why would Armand not reveal to his sister that he is working with the Scarlet Pimpernel?
2.Before her marriage, Marguerite was an actress. Why would the author assign that particular career to her character?
3.The author gives us a detailed account of Sir Percy’s wardrobe. Why would that be important?
4.What do Chauvelin’s clothes reveal about him?
5.Marguerite claims to have been tricked into denouncing the M. de St. Cyr. Do you believe her?