Is it permissible for the agent to spend the money on something other than what he was entrusted with?

Q: If a person collects money or donations and informs the donors that it is for the furnishings of a Quran memorization center outside the country, and also to buy Qurans and religious books for this center, and that is the case, but the amount exceeds the need, is it permissible for him to:
Buy a recorder and Quran tapes with the remainder for the center so that the students can benefit from them?
Give the remaining money to a person who wants to build a mosque, thereby contributing with him, even if it is only a part of it, without the knowledge of the donors? What is the ruling?

A: It is obligatory for him to spend what he received from the donors for the benefit of the center, such as furnishings, books, and the like. He is not permitted to spend any of it on another center or another mosque, because he was not entrusted with that. And success is from Allah.