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.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

energy and particles