How is the Zakah(obligatory charity) on articles of merchandise calculated?

(2.5%) of each article`s value is paid as Zakah after a whole lunar year had lapsed.

For passing time, my friends and I have called a famous diviner. She told me that somebody had cast a spill on me not to get married for the rest of my life. I didn`t believe her, but I can`t forget her words. How can I protect myself from such thing?

Praise be to Allah the Lord of the Worlds.

Dealing with diviners is forbidden and what you are suffering from is due to your having consulted that diviner. Have trust in Allah and ask Him for forgiveness, but rest assured that whatever Allah has decreed will take place. And Allah The Almighty Knows Best.

Is a wife considered sinful if she asked for divorce because her husband married another woman?

A second marriage is lawful, and so it is impermissible for you to ask for divorce because of that. If you are certain that you won`t be able to deliver Allah`s rights and those of your husband`s , then it is permissible for you to ask for Khul`a(Divorce on the demand of the wife). However, you should exercise patience since after difficulties, there is easiness by the will of Allah.

Is it permissible for a woman to apply Kuhul (Halal eyeliner) and go out wearing it?

Kuhul is part of a woman`s adornment, and it is forbidden for her to show that to anyone other than a husband, or a Mahram (Unmarriageable kin).