Islam does teach that Adam ate of the tree, but Islam does not teach that sin is hereditary.
No, Neither Adam nor any prophet founded Islam. Allah (God in English) is the founder of Islam. Refer to question below.
Islam was not discovered. It was the first religion sent to Adam.
No
They can.
Historically, the prophet of Islam was Prophet Muhammad. But in Koran it is said that Adam was a Muslim too. So, either Adam or Muhammad.
Islam actually started at the point when God let down Adam and Eve. It was Adam's duty to have to teach the wilderness people how humans live properly and to pray to God. There on, God sent down thousands of prophets for spreading Islam. All those prophets were assigned for specific civilizations. The last prophet was Prophet Muhammad (peace be upon him). He was the prophet for humanity. He was to teach the world about Islam and introduce the last of the five Islamic books, the Quran. Angel Gabriel, was to tell him about the things God (Allah) assigned him to tell his followers. Therefore, Islam was spread and Muslims are today constituting more than 1600 millions.
yes
yes
According to Islam first prophet was Adam.
From the beginning of Creation. From Prophet Adam.
Adam (peace upon him)