A mahram is an unmarriageable kin with whom marriage or sexual intercourse would be considered haram, illegal in Islam, or people from whom hijab is not obligatory.
as salam alaikum
The rules of mahramiyyah apply to all mahrams: those mentioned in the ayah and those who are not mentioned.
With prayers for your success.
Thank you for your question. There is no problem with this unless you fear falling into sin.
May you always be successful
Yes it is allowed to expose her feet only , not any part of her leg, if the men who can see her are her own Mahram like father, son, real brother etc. Muslim female must cover her feet even during performing Prayers if any non Mahram man can see her while she is praying.
It does need mentioning that covering the feet is part of compulsory Hijab in front of non Mahram man.
According to Islam all humans are the servants of Allah and slavery is wrong. However the time of Prophet a lot of people were slave and slavery was acceptable in the world. Islam started to teach people that it is wrong and to free the slaves step by step . First Islam gave them rights and made rules to support them....
Anyway according to Islam the female slaves were like the wife of the owner and the male slaves were mahram.