Is washing the private part after urinating (Istinjaa`) a condition, and is it done with water and soap, or with water only?
Istinjaa` is obligatory for removing impurity, and it can be done with toilet paper, or a stone, or water. It is preferable to do Istinjaa` first with paper, or stone, or the like, then to wash the private part with water until making sure that the impurity has been removed. Using soap is not a condition, but there is no harm in doing so provided that it is washed off with water. It is also permissible to use either water, or paper if impurity is removed by any.
Is it permissible for a father to divide his property amongst his children except one under the pretext that he has paid for the latter`s tuition? This is knowing that his other children were given the opportunity to pursue their education but didn`t because they were educationally poor. Moreover, is he allowed to give his other children who have helped him with growing his business?
All perfect praise be to Allah the Lord of the Worlds. May Allah`s peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
The father should be just between his children as regards gifts, in case they had similar circumstances. However, if any had a special merit, then it is permissible for the father to take that into account to be just. For example, giving his children who have helped in making his fortune and received no reward for that or giving the little ones because they haven`t taken as much as the older ones or giving the sick child who is unable to make a living. The most important thing is achieving justice. Moreover, the father is not interdicted by any of his children, and he is free to do whatever he wants with his money and Allah will call him to account as regards observing justice between his children. And Allah The Almighty Knows Best.
Is buying shared land from someone who has taken possession of it considered halal or haram?
The shared land is possessed by the country i.e. for all people; therefore, it shouldn't be possessed/occupied save by it's guardian/owner permission,thusly it can't be possessed save by having owners' permission. Finally, buying it from a person who don't possess it is impermissible. And Allah Knows Best.
Is it permissible for someone to make a supplication to Allah to marry an already married, or an engaged woman?
No, it isn`t, and the person who does so is sinful before Allah, The Almighty.