well you woulda got your answers if you take a look at the Basic ideas of the information i posted,
1) Miracles (Qur'an, Illiterate man, others..)
2) Prophecies cannot be lies
3) Characteristics of the Human (use common sense)
4) and Basic Characteristics of previous prophets. ( again common sense)
5) I dont know y u ask if we can tell will be one or not because Prophet Muhammad (PBUH) was the seal of prophets it was stated, so there is no point if sumeone says he is a prophet because we all know he was lying because Allah said Prophet Muhammad (PBUH) would be the last one . If you noticed he was the LAST PROPHET. Did you notice any other major historic figure that agreed with the previous books and claimed he was a prophet?
In conclusion, Prophet Muhammad (PBUH) was all of that.