4.
In a certain code language, 'A + B' means 'A is the daughter of B', 'A โ B' means 'A is the brother of B', 'A ร B' means 'A is the wife of B' and 'A รท B' means 'A is the father of B'. Based on the above, how is P related to T if 'P + Q โ R รท S ร T'?