Today in class I suddenly had a brilliant idea for a new invention:
Make a cheap, portable small box with a solar panel on the top. Inside the box make a little machine which extracts carbon from carbon dioxide (I don’t care how, make it cheap and simple). Now the box spouts out oxygen and deposits carbon inside a little waste box which you can clean every month or so. All for free since it’s solar powered.
Then I noticed a fatal problem: this already exists.
It’s called a plant.