What is the ruling of Islamic Law on colleagues alternating overtime shifts and receiving wages for absent days?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
An employee is religiously obligated to abide by the instructions and regulations pertaining to overtime hours. Furthermore, it is mandatory to adhere to honesty and avoid deceit, circumvention, and falsehood. Allah Almighty says (what means): "O you who have believed, be conscious of Allah and be with those who are truthful."
(At-Tawbah/119).
Therefore, whoever is assigned to work overtime must remain present at the designated workplace, even if no active tasks are required of them during that time.
Likewise, the official authorized to approve overtime work must comply with all established conditions and regulatory guidelines. It is impermissible for them to grant overtime hours in violation of system regulations. Should any compensation be disbursed in contravention of these official rules, it is unlawful to accept or consume such wages. And Allah Almighty knows best.
Is it permissible for one to give the Zakah (obligatory charity) to his indebted brother?
It is permissible for one to give the Zakah to his brother if he was indebted, or poor.
Is it permissible for a mother to stop her daughter from marrying a respectable, God-fearing young man because he isn't college/university graduate?
It is impermissible to deny a woman her right in getting married except for a lawful reason, and problems can be solved through dialogue. However, she can file a suit in order for the judge to have a say in that regard.
What is the ruling on water present on the floor of a toilet/bathroom?
The default ruling is the purity of this water present on the bathroom floor. If one is certain or strongly suspects its impurity, then one washes whatever part of the body or clothing this impure water has touched. If one doubts its impurity, the default is purity, and we do not rule it impure based on mere doubt. And Allah the Almighty knows best.