Is it permissible for a woman to pray sitting in a car due to the absence of a place where she can seclude herself from men for prayer? And is sea water pure for ablution, and is it permissible to relieve oneself (small an-najasa) in it?

A woman is not permitted to perform the obligatory prayer while sitting merely because the place is exposed to men. She must repeat the prayer if she has done so, because standing is a pillar (rukn) that is not waived by such a pretext.

As for seawater, it is pure (tahūr) and removes both major and minor ritual impurity. It is permissible to purify oneself with it by consensus, based on the Prophet’s (peace be upon him) saying: "Its water is purifying, and its dead are lawful." There is no harm in relieving oneself in the sea, as it is not affected by impurity.