Is it permissible to deduct the remaining amounts of car and apartment installments before calculating Zakat? And is it permissible to calculate Zakat on the profits of investment certificates at 10% monthly instead of 2.5% on the principal amount? And is it permissible to give Zakat to a brother to help him with marriage, medical treatment, paying his son's expenses, and his deferred divorce payment? And is it permissible to buy gifts for relatives from Zakat money upon returning from travel?

The answer is summarized as follows:

1. There is no harm in giving out Zakat in Ramadan before the due date (hawl), if the wealth has reached the nisab.

2. It is permissible to deduct the remaining debt from the price of the car and apartment from Zakat funds if there are no other funds available that exceed one's needs.

3. The amount of Zakat due is a quarter of a tenth (2.5%), and any amount exceeding that is considered a voluntary charity (sadaqah nafilah).

4. It is permissible to give Zakat to a brother if he is in debt (gharim) and unable to repay it, or if he is poor (faqir) or needy (miskin), provided his need is verified, and it is not permissible to give it to someone capable of covering his own expenses.

5. It is not permissible to use Zakat funds to buy gifts; rather, they must be spent only on their legitimate beneficiaries as prescribed by Sharia.