Is the `Iddah (waiting period) of the divorced effective from the time the divorce took place, or from the time of registering it at the court?

It is considered effective from the very moment her divorce took place, but not from the time of registering it at the court. And Allah Knows Best.

I am an author, and I have books stored with me. Is it permissible to pay my zakat in the form of books containing beneficial knowledge for poor students, such as chemistry and mathematics, or religious books that spread Islamic sciences?

Zakat on wealth must be paid in cash from the wealth itself. Therefore, you should pay your zakat in monetary form so that the poor can purchase what they need. And Allah Knows Best.

Is it permissible for me to name my daughter “Leen”?

“Leen” means “ease”, and there is no harm in giving your daughter that name.

My husband wanted to sell a piece of land that was his own, but his father insisted that he transfer the land in his (the father’s) name so that he could sell it at a higher price. Then, my husband and his father would split the price. After my father-in-law sold the land, he denied everything and refused to acknowledge my husband’s right. My father-in-law passed away a year ago, and my husband’s brothers divided the inheritance, refusing to acknowledge that this land was a trust held by their father for my husband until it was sold. Are they sinful for knowingly denying that the land belongs to my husband, and what is the ruling on praying against them?