It's acquired. Innate means you have it at birth, acquired means you picked it up. Obviously babies can't speak ;) so it's acquired.
No. A mirror works because of reflection.
Answer:
I am pretty sure its the second one but I could be wrong sorry if I am.
Explanation:
:D
We can't tell without more information. We know it will be higher than 40 and lower than 75, but we don't know exactly where it will settle. In order to work that out, we would need to know the volumes of the water and the cube, and WHAT metal the cube is made of.