Is it permissible to give lessons to mixed students of the seventh grade?

It is impermissible to give private lessons to mixed students since such an act leads to serious consequences for the students in this grade are teenagers.

What is the ruling on reciting verses of the Holy Quran on water, then drinking it?

It is permissible to recite Quran on water, then drink it as a kind of treatment since the Quran heals. Allah, The Almighty, says:” We send down (stage by stage) in the Qur’an that which is a healing and a mercy to those who believe: to the unjust it causes nothing but loss after loss.”{Al-Isra`/82}.

I`m a building contractor. I have been building a house for a client, but the construction process stopped for some reason. Unfortunately, currently, prices of materials have multiplied, is it allowed for me to demand an increase in the agreed price?

I`m a cashier at a branch of the Civil Service Consumer Corporation. Sometimes, customers pay more than the due amount. Do I have the right to take that extra money knowing that I cover shortages from my own salary?