Well, when you're off to work, under the road or under the buildings that you see, there might very well be cellular concrete, which is a very light kind of concrete that's actually got proteins from bones inside and it's also fully reusable.
Pa, kad krenete na posao, ispod ceste ili zgrada koje vidite zasigurno se nalazi šupljikavi beton, koji je vrlo lagana vrsta betona koji zapravo sadrži koštane proteine u sebi, i ujedno se može višekratno koristiti.