What 2 wave principles are illustrated by black car seats getting hot when the sun is shining through a window?

1) black body radiation

2) Electromagnetic radiation through the window

Explanation:

Blackbody radiation is the radiation produced by heated objects, particularly from a blackbody. The car is heated by sunshine. Actually, everything is heated by sunshine, and the car being a blackbody  object absorbs all radiation (visible light, infrared light, ultraviolet light, etc.) that falls on it. This also means that it will also radiate at all frequencies that heat energy produces in it.

Radiation from the Sun is absorbed, through the glass, by the inside of the car. That is why it helps to have tinted glass or use a screen on the windows while it is parked.

conservation of mass

mass before something happens = mass afterwards