What is sincerity, and what are the benefits of sincerity?

I would like to know the proper way to make du’aa’ during prayer, as the Prophet (peace and blessings of Allaah be upon him) did it. Is it after the prayer or between the two prostrations or whilst standing or when?.

In Sahih Bukhari, it is mentioned that ...70,000 of all mankind will enter paradise(!!!)
The first three generations of muslims alone probably amounts to 70,000.
Is there another explanation to this hadith?

Do we get rewarded by Allah in this world not only the next.. Meaning Allah will reward us in life for doing good deeds and also get more reward in the hereafter.

I am a young Muslim man who believes in Allah and His Messengers and His Books, praise be to Allah. But sometimes I feel too lazy to pray. I am looking for a solution and a way to make me not be so lazy. Please note that this is what I want but the tricks of the Shaytaan are too strong.

I was just wondering if someone says he will drink and do zina (fornicate) and do haram (unlawful) stuff and then he will repent, will his repentance be accepted?

What is the Islamic ruling on the issue of imitating the kuffaar in their customs and dealings? What are the guidelines concerning that in Islamic sharee'ah? Is every imitation of the actions of the kuffaar regarded as a haraam kind of imitation, knowing that there are many things that the kaafirs do that are not haraam and are not condemned by sharee'ah, where the one who does them does not do them merely to imitate the kuffaar, but because he thinks those things are good, as Ibn Mas'ood (may Allah be pleased with him) said: "What the Muslims think is good is good before Allah"?  
Please advise us, may Allah honour you, and please give me a detailed answer and explain to me the guidelines on this matter.

A non-Muslim friend of mine asked how I could prove the existence of God and why He has given us life, and what its purpose is?
My answer did not satisfy him, please tell me what I should tell him?

Question:

I have a few questions concerning parents
1-What right does my Mother have over me?
2-What right do I have over my mother?

Will a person (a believer) be rewarded if he listens to the Qur’aan without understanding what he is listening to, but he knows that it is Qur’aan? Or will he not be rewarded unless he understands what he is hearing? I hope you could give some evidence from the Qur’aan and saheeh hadeeth.

I am doing research on the concept of monotheism in the world's five major religions. Could you please explain to me the concept of monotheism in Islam?
 

Is it mustahabb to say Qunoot during the daily prayers for our brothers in Gaza, so that Allaah will relieve them of the aggression of the Jews? In which prayer should Qunoot be said?