Which type of water is the least dense?

a.
warm, salty water

b.
warm water with no salt

c.
cold water with no salt

d.
cold, salty water

B, cold with a high salt content, I believe. Since density is mass divided by volume, adding salt would increase mass. Temperature is related to kinetic energy and the distance between molecules/atoms of a substance. The hotter the substance, the more distance there is between particles. Generally cold water is more dense. Hope i helped :D

the real answer is b. scintillation counter