Ultraviolet rays. a). Is the major cause of skin color evolution

b). Is strongest at the equator

c)Can penetrate the skin and helps produce Vitamin D

d). All of the above

What is the force of attraction between the particles in a salt crystal

Complete the following statements to describe solids, liquids, and gases. select the correct answer from each drop-down menu. a solid a definite volume and a definite shape. a liquid a definite volume and a definite shape. a gas a definite volume and a definite shape

Elements in group 2 are all called alkaline earth metals. what is most similar about the alkaline earth metals?