Purdah

Non-mahram approaching a group of ladies

Q: If a female is among a group of other females and a non mahram male approaches the group of females to speak to the other females she is in the group with, is it enough for this particular female to lower her gaze and refrain from useless chatter with the male while still standing in the group or is she supposed to leave the gathering when the male approaches?

Exposing one's satr in a room wherein there is an Islamic calendar

Q: I always put Islamic books away and don't leave them uncovered incase they get disrespected. I would like to know if an Islamic calendar with no Quraanic Ayahs or Hadeeths are on there, and it just says "Islamic calendar" and has dates are hanging in ones bedroom and if one dresses really immodest like nude and seminude etc. is it disrespectful? And what is the ruling if one thought that it might be disrespectful but ignored the thought and continued to leave the calendar hanging?