When placed in a 100 ml cube-shaped box, a substance fills the cube and has a volume of 100 ml. when placed in a 50 ml tube, that same amount of substance fills the tube and thus has a 50 ml volume. what is the state of the substance?

The substance is a gas.

The substance takes both the shape and the volume of the container, so it must be a gas.

*tilts head* sounds more like a statement

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).