If one substance floats in another it must be dense

True
Or
False

true

Explanation:

Density is the only thing affecting whether something floats or sinks. If an object has a higher density than the fluid it is in (fluid can mean liquid or gas), it will sink. If it has a lower density, it will float. Density is determined by an object's mass and volume.

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

answer; the code in musculoskeletal system subsection is associated with deep tissue possibly to the bone;