Hi! :)
The amount of uranium within nuclear fuel rods is enough to sustain a chain reaction but is less than the critical mass necessary for the reaction to become explosive.
In ancient times, people classified plants and animals by use. Like for plants they are being classified as beneficial or harmful. While for animals, they are classified as domestic animals, wild animals, creeping animals, flying animals, and sea animals.
Filtered blood leaves the kidney through the renal vein and flows back to the heart. Pee leaves the kidneys and travels through the ureters to the bladder. The bladder expands as it fills.
It’s the subsoil layer. Hope this helped :)
