Which statement best describes elements ?
a. they are the smallest particles of any material.
b. they are composed of only one type of atom.
c. they are the most expensive materials on earth.
d. they break down easily

Diffraction is when light is bent around obstructions. which of the these observation about clouds would indicate diffraction? a) after rain storms, you can sometimes see rainbows. b) clouds are white or gray and cannot be seen through. c) on a cloudy day, the temperature tends to be cooler than a sunny day. d) the edges of dark clouds appear lighter. this