Supplications

There are two type of decree; changeable and unchangeable. The unchangeable one, only Allah knows about. The changeable one is the one we can change through Dua’a and other deeds.

This is forbidden and it is an innovation.

You can say the supplication which prophet Musa alaihi salam said: Rabb-ishrah ii sadri, wa yassir li ‘amri, Wah-lul ‘uqdatam-mil-li-saani, Yaf-qahuu qawlii O my Lord! Expand me my breast; Ease my task for me; And remove the impediment from my speech, so they may understand what I say [Surah Ta-Ha; 20:25-28]

There is nothing specific only the general dua’a and this ayah as well “And those who say: “Our Lord! Bestow on us from our wives and our offspring who will be the comfort of our eyes, and make us leaders for the Muttaqun””

There isn’t any specific hadeeth in this regards but the general rule is that when a person is in distress, Allah answers it.

It is permissible after a lecture to raise the hands when making Dua’a.

He must say the dua’a before entering in the toilet اللَّهُمَّ إِنِّي أَعُوذُ بِكَ مِنَ الْخُبْثِ وَالْخَبَائِثِ “O Allah. I seek refuge in You from the male female evil and Jinns”.

Yes, you can,but if you repeat after the muadhin you are rewarded

Correct.

Abdullah Ibn Mas`ud (May Allah be pleased with him) reported that the Prophet (salla Allahu alayhi wa ssallam) used to say: “Allahumma inni as’alukal-huda wat-tuqa wal-`afafa wal-ghina (O Allah! I ask You for guidance, piety, chastity and self-sufficiency)”. Muslim