Is it permissible for one to shake hands with his uncle`s daughter?
No, it isn`t because he is a non-Mahram (Marriageable) to her.
In the last verse of Surah At-Tin, Allah Says (What means): "Is Allah not the most just of judges?" [At-Tin/8]. Is it permissible for us, while performing congregational prayer, to respond after the Imam recites it by saying: "Indeed, and I am among those who bear witness to that." ?
It is recommended for the worshipper to say 'Indeed' (Bala) silently after reciting or hearing the verse (/What means): "Is Allah not the most just of judges?" [At-Tin/8]. This is part of reflecting on the Quran during its recitation or listening, as Allah Says (What means): "Then do they not reflect upon the Quran, or are there locks upon [their] hearts?" (Muhammad: 24). Doing so helps in achieving humility and focus in prayer. And Allah Knows Best
Does passing wind from the anus affect ritual purity?
Ablution is nullified by the passing of wind from the anus, but washing the anus is not required as wind leaves no impurity.
What is Aqeeqah?
It is the sheep slaughtered on the seventh day from the child`s birth, and it is a confirmed Sunnah after the Prophet (PBUH).