Some Rulings of Iddah

Summarized Fatawaa

What is the wisdom and purpose behind the 'aqīqah?

All praise is due to Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
Among the wisdoms and purposes of the 'aqīqah are the following:
First: Expressing joy at the blessing of Allah the Almighty, rejoicing in the newborn, and giving thanks to Allah for this gift. Allah the Almighty says (what means): "If you are grateful, I will surely increase you." [Ibrāhīm/7]
Second: Proclaiming and publicising the lineage (nasab) of the child — and the 'aqīqah serves as an appropriate and fitting means to this end.
Third: Gladdening the hearts of family members, relatives, friends, and the poor by gathering them together over a shared meal. And Allah Almighty knows best.

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.

What is the ruling on objecting to the Mosque Imam regarding the joining of prayers due to rain?

 
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
 
It is not permissible for any of the congregants to object to the Imam in the mosque, whether the objection is to demand the joining of prayers or to oppose it; for the general principle is that the Imam possesses the religious knowledge (Al-Ilm al-Shar‘i) that qualifies him to make the decision in this matter. And Allah the Exalted knows best."

Is bleeding that lasts for nine or ten days considered menstruation (Hayd)?

Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
 
If the duration of the bleeding does not exceed fifteen days, then all of it is considered menstruation (Hayd), even if the regular cycle ('Adah) has changed. And Allah the Exalted knows best.