Should nail polish be removed before making ablution?
Yes, it should be removed because it prevents water from reaching the nails.
Can a woman leading other women in Tarawih prayer recite aloud?
Yes, a woman leading other women in Tarawih prayer is allowed to recite aloud, as long as no non-mahram (other than unmarriageable kin) men can hear her.
Who is responsible for performing the aqiqah?
All praise is due to Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
The one upon whom the 'aqīqah is incumbent is whoever is obligated to financially maintain the newborn — whether the father, paternal grandfather, or mother. It is to be performed from their own wealth, not from the wealth of the newborn child.
As for one upon whom the financial maintenance of the newborn is not obligatory, they may not perform the 'aqīqah except with the permission of the one upon whom it is obligatory — namely, the father. And Allah Almighty knows best.
Is there a solution to put an end to thinking of worries during prayer?
Firstly, make ablution after the time for prayer begins and busy yourself with remembering Allah, The Exalted, before the iqaamah (start of prayer).In order to become humbly submissive during prayer, you must perform prayer in congregation. After the prayer ends, stay in your place and read the post-prayer remembrances (Adhkaar) and make supplication to Allah, The Exalted.