weight of responsive jpg, how big each img depending on screen resoliution??

Hello, I want the web to show one or other image depending on the screen resolution.

The first thing I have clear is that 72dpi is enough.

The next thing is how many versions of the same picture do I load?

My suggestion is this one:
@media screen and (max-width:1680px)
@media screen and (max-width:1280px)
@media screen and (max-width:980px)
@media screen and (max-width:736px)
@media screen and (max-width:480px)
.@media screen and (max-width:360px)

Too much, no?

The next thing and more important is the quality of each version of the same image for each screen resolution.


Thanks alot