An electronic music speaker, amplifier or sound system.

Speaker

A poster or sheet of paper with tape pasted diagonally across the ccreatiorner.

Poster

A person sitting down, with his computer and headphones, participating in an online class, watching a movie or listening to music.

A storage box containing sheets of paper.

A round retro vinyl or a CD with a hole in the middle to play music. 

A person sitting down while holding a very long sheet of paper.

A busy and overworked manager or employee surrounded by charts, graphs, and notifications.