How much time does it take to tour the museum?

As little as an hour if you're just looking. If you're reading everything and talking to the people that work there, you could spend a couple days.

I would say depends on the person has will, it took us like 3hrs and we did not do everything

Four hours was not enough for me but I also ran out of film!

I'd agree, as little as an hour , probably 3 hours max if you really take your time!

I would say about 2 hours.