You can spend as much time as you like, but be aware that the last entrance is at 6pm and they close at 8pm during the week. Also very large tourist groups seem to show up between 2 and 4. Also signage to exit the museum is fairly vague. No one offered me a map.
Yes. Till 8pm
No no one offered me a map and I asked. Then as we were leaving I found. So I'd ask for a paper map
Nope you can spend as much time as you want
Nop. You can take all the time you need see the memorial
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