Salaah

Second jamaat in the musjid

Q: There is a masjid inside a university where many Muslim students live, but it often does not have any jamaat salaah on Sundays, though the Friday prayer is held there.

An imam is appointed for the masjid, but he often does not come for Fajr, Isha and prayers on weekends (maybe because he lives far from the university). When the imam is not present, anyone leads the prayer. Is it correct to start a 2nd jamaat after the imam has already led the 1st jamaat salaah?

Performing salaah with a thin scarf

Q:

1. When I tie a scarf around my head to pray, it sometimes moves or my hair can be seen through the material or my shoulder or neck can be seen through as it is slightly (not very) see through because of this I feel my prayer has been invalidated. Is this true? I of course wear clothes under the scarf but if the scarf is slightly see through, will this invalidate my namaz?

2. All the namaz I have been reading with this scarf, so if my namaz is invalid, would this mean my nikah would be invalidated?