What explains why human eyes come in a variety of colors?

If equal masses of the listed metals were collected , which would have a greatest volume ? a. aluminum 2.70,b.zinc7.14,c.copper 8.92,d.lead 11.34

In a water molecule, hydrogen and oxygen are held together by a(an) bond. a) double covalent b) ionic c) nonpolar covalent d) hydrogen e) polar covalent

How can a give a full method for the experiment of separating sand from water by filtration? 1-materials 2-steps 3-conclusion also for water and salt separated by the evaporation or distillation process