What is a picture plane?

Hello darlings! could anyone explain to me what exactly this means? i can't understand exactly what my school is asking of me oof i've read the lesson over and over and i'm still confused. create your own nontraditional artwork. you might choose installation art, environmental art, or use an unconventional medium.

What convetion did chardin and delacroix use in the painting grace before meal and liberty leading the people to give the artworks a sense of harmony and stability?

According to the article in wiki answer, digital communication systems have more benefits than analog systems. they are faster and more flexible, and they offer better performance than analog communication