Sayyed Mohammad Al-Musawi

The prayer will not be invalid but it is always better to keep our intention concentrated in our Prayers during performing Salah.

Wassalam.

Simply, make water reach your head and face and neck then your right side of your body, then the left side of your body. Obviously after having in your heart the intention of Ghusl for the sake of Allah (SWT).

Wassalam.

Saying all the Takbir and other sayings in Zuhr and Asr aloud is permissible. Reciting the AlHamd and the other Sura should not be aloud in Zuhr and Asr. Reciting Bismillah Arrahman Arraheem aloud is recommended in Zuhr and Asr, while it is obligatory in Maghrib, Isha and Farr prayers.

Wassalam.

He has given the option of Musalaha (mutual agreement) to make the transaction lawful. Please get the exact translation of the text to understand the rules of it.

Wassalam.

Supporting any company which supports killing the innocents is forbidden and the income earned from wrong is unlawful. You as a Muslim should support the innocents or at least refrain from supporting their  murderers. We trust that our Rizq (sustenance) is from Allah only and not from others, so, we seek lawful income from Allah (SWT) only.

Wassalam.

The earning of Halal income depends on the nature of the business or the service. You must be sure that your business or service is really Halal, then you don't need to worry.

Wassalam.

If you find out that any part of your income is unlawful (Haraam), you must give it back either to the real owners of it, and if you can’t reach to the real owners, then to the Muslim authority ( Haakim al-Share who is the Marja; of Taqleed) to give it to the poor as Majhool al-Malik (unknown owner fund).

Your late knowledge about the Haraam does not release you from your responsibility to give it back totally including what you spent from it.

Wassalam. 

Any man who commits the major sin of fornication with a married woman will be forbidden from marrying her for all his life. He can marry with another woman if she agrees but not that woman with whom he committed the crime of fornication while she was married even if she is now divorced or widow.

Wassalam.

As far as the believer Is fulfilling his duties and avoiding sinful acts and thanking Allah (SWT) for His bounties, he will remain blessed in this life and hereafter. Trials are best known to Allah (SWT) but if you don't have any hardship, it does not mean that your faith is worthless as far as you are worshiping Allah properly, avoiding sins and thanking Allah (SWT).

Wassalam.

Everything is Taahir for you unless and until you know for sure that it is Najis. Doubt about Najasah does not mean that the doubted item is Najis with out concrete evidence. If you have concrete evidence that a specific item is definitely Najis, then you can make it Taahir by pouring water in it.

Wassalam.

Sexual toys are not permissible in Islam whether used for external play or otherwise. The permissible sexual activity is between husband and wife and not with a toy or anything else.

Wassalam.

As a virgin Muslim girl, you need your father's or your paternal grand father's approval for your marriage. If your father's refusal is based on un Islamic reasons, then you might try convincing him through your relatives of family friends who can talk to him. You should always keep the respect for your parents and never utter  a word which can harm their feelings. 
In case your father insists on rejecting for un Islamic reasons, you can refer to you Marje' of Taqleed and seek his advice or verdict after explaining your situation.

Wassalam.