Women's satr exposed in salaah

Q:

1. I now wear 2 khimars, 2 shalwars, 1 half-sleeve T-shirt underneath two kurtas, and a pair of gloves (and I try my best to tuck in the sleeves of the 2 kurtas into them) until the wrists because my clothes are thin and quite see-through. After wearing these clothes, I feel comfortable, Alhamdulillah, that the satr is not going to be seen.

My question now is that if a woman goes into sajdah and if she is wearing a see-through kurta (and no other shirt) and even though her khimar (which reaches almost until her knee cap when she is standing) still covers her body during sajdah by draping around it but does not cover the kurta itself such that if someone (like an angel or a jinn) were to watch her from below the ground, they would see the kurta uncovered by the khimar but someone standing on the ground could not see anything underneath the khimar at all. Does this invalidate the prayer?

2. If two limbs are exposed during Salaah, each less than a quarter of its whole area, how can a woman know if it invalidated her prayer? What is the length she can measure to?

3. If a woman wears shalwar (which kind of shows her figure but is not figure-hugging like tights), then is her Namaz valid?

Man's "authority" over his wife

Q: When speaking of the qiwamah of a man over his wife (i.e. his “authority” over her), we need to realize that this is a burden and a responsibility, not an honour and favour. The man’s responsibility is not restricted to maintaining his wife financially, housing, feeding, etc. He is also responsible for looking after her emotional, spiritual and physical needs. Allah’s command is to treat wives kindly and on a footing of equity and what is acceptable. وعاشروهن. Al-qiwamah is in no way meant to turn the husband into some sort of dictator who thinks he is a master who orders and forbids and should be obeyed unrestrictedly. There are so many nuances to look at when we look at these issues. One such nuance is that Allah did not say that males are qawwam over women; rather, He said “men” are qawwam. This is something we need need to think about and ponder; for how many males are not really “men”.

Is this above writing correct? If I feel like for my husband's thinking attitude is harming my imaan, I often think bad of Islam that it favors men over women should I leave him?

Wishing for one's non-Muslim girlfriend to accept Islam

Q: There is a Hindu girl that I like and I wish to marry her in the future (we both are 16 years old) as I don't want to have any haraam relationship with her. Is there anything I can do to inspire her to embrace Islam with her heart, mind and soul so I can marry her?

I genuinely care for her and I don't want her to go to hell because she is a very good, generous and honest girl. Please guide me in this matter. I can take things slow and cautiously with her if I can inspire her to embrace Islam.

Creation of the earth and theory of evolution

Q: How was the earth created by Allah Ta'ala?

Did Allah Ta'ala create all the animals and species that are present in the world today or have the species gone through evolution that made them so numerous?

Was the world that is today the same as when it was created? How long ago (in years) was the world created?

Was there a time when there were no humans in this world?

Were there dinosaurs in this world?

Also, I know that evolution through ape-like is not correct, but Darwin also says that birds and other animals have evolved. So for example, how there were birds with a certain type of beak but now those birds are on different places where their food is different so their beaks "evolved" into different shapes depending on whichever suited their environment better. Can we as Muslims believe this or not?