Does diarrhoea make it permissible for the fasting person to break his fast?

I would like to know some of the ahaadith which speak of the virtues of Jumu'ah prayer.

When a person repents, he makes a vigorous start and says: "The Shaytaan is telling me to slow down", so he does more acts of worship. Then his enthusiasm cools down, and he says: "Allah does not burden any person beyond his scope", and his acts of worship become less until he goes back to the way he was. 

My question: What advice can you give? Should he make a vigorous start, or take a gradual approach until it is established and then add more after a while, or should he follow the saying: "When your wind blows, then make the most of it"?.

What are our duties towards our Muslim brothers who have been stricken by calamities and disasters throughout the world?

If the sin involves the rights of another person then what form should repentance take?

I have repented. But in my possession are some forbidden things such as musical instruments, cassettes, films, etc. Is it permissible for me to sell them, particularly since they are worth a large amount?

I forgot that I did not have wudoo' and I prayed. After I finished my prayer, I remembered that. Do I have to repeat my prayer?

I read the words: "The scholars are unanimously agreed that fatwas may change according to time, place, local custom and situation so it is essential to take new developments into account". But I am not convinced of this. Is this view correct? I hope that you can answer with evidence from shareeطah and the Sunnah. May Allah reward you with good.

Is it permissible to buy an apartment from the bank by instalments?

I have a question regarding the permissibility of becoming a law enforcement officer in this country that does no follow sharee 'ah. Is it haraam to be enforcing laws that have not been developed by our Creator Allaah and His holy Prophets (upon whom be peace)? Even if it means enforcing laws on non-Muslims?

Partciluarly, is it permissible to enforce a law like punishing someone for speeding on the highway? What about allowing someone to drink alcohol if he is over 21 but not if he is under 21? Even though this is not Islamic, should a Muslim allow such behaviour among non-Muslims? Of course, Muslims will be accountable for these haraam actions in the Hereafter, but is it okay to let non-Muslims do this?

What is the ruling on mixing with kaafirs and dealing with them kindly, hoping that they will become Muslim?