What is the difference between redshift and blueshift?

Redshift and blueshift describe how light shifts toward shorter or longer wavelengths as objects in space (such as stars or galaxies) move closer or farther away from us. The concept is key to charting the universe's expansion. Visible light is a spectrum of colors, which is clear to anyone who has looked at a rainbow.

Explanation:

characterization of nanoparticles is a critical step in nanomaterial production as it provides information of dimension, morphology, surface charge, distribution and degree of surface functionalization.

if you add everything up correctly you should get 69 i got this because 50 plus 19 is it