Is Iddah (waiting period) incumbent on an old lady whose husband had died?

Upon the death of the husband, Iddah is incumbent on the wife regardless of her age.

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 wear colored lenses?

All Perfect Praise is due to Allah, The Lord of The Worlds.

Wearing colored lenses for treatment is permissible, and wearing them as an adornment is also permissible, provided that she isn`t seen while having them on by non-Mahrams (Marriageable men). And Alalh Knows Best.

What is the ruling on taking part in an online contest to win a prize of 100,000 dollars in return for answering thirty questions in different fields of knowledge and science? This is knowing that there is no drawing of lots; only one or two cards are purchased to commence the contest.