Is touching a non-Mahram woman invalidates person's ablution?
Touching non-Mahram woman is prohibited, and according to the Shafiee's, it invalidates the ablution. And Allah Knows Best.
What is the ruling on having brotherly ties between a strange man and a strange woman, and is the former considered a Mahram (unmarriageable) to the latter?
Such a relation between a strange man and a strange woman is forbidden in Islam because it involves forbidding what Allah has allowed by marriage, and allowing what Allah has forbidden such as looking and the like. Such a relation doesn`t render any act lawful between them, thus they are forbidden to look at each other, have a Khulwah (seclusion), and travel together.
What is the ruling on someone who perform their prayer after finishing it because they believe they missed a Rak'a, a prostration, or that they did not perform it correctly (thinking their prayer was invalid)?
If he was sure that his prayer is void then reperforming it is an obligation along with figuring out the reason of invalidity so long as this wasn't out of uncertainty. And Allah Knows Best.
I went to the health center today to take an intramuscular injection of Neurorubin B12. The nurse told me that this type of injection breaks the fast because it nourishes the body. Is this true? I have heard that intramuscular injections do not break the fast, but I was unsure about this type, so I decided not to take the injection.
Therapeutic injections administered subcutaneously or intramuscularly do not invalidate the fast because they do not enter the digestive tract through an open passage. However, intravenous injections containing nutritional fluids do break the fast, as they are akin to food and drink in effect. The B12 injection is a therapeutic injection and does not break the fast. And Allah Knows Best.