Is it permissible to explain lessons to women in a mixed-gender university, whether through direct meeting without seclusion or via telephone?

It has been previously explained that studying in mixed universities is dangerous, and that the original ruling is that it is impermissible except in cases of necessity or need, while observing the Sharia (definition) controls. Conversation between a man and a non-mahram (definition) woman is originally permissible when there is a need, but it can involve risks, especially with a young woman, hence the jurists have emphasized caution in this regard. It is obligatory to be careful and avoid anything that leads to temptation. The girl can search for a female colleague to explain to her, or any other legitimate means.