Blue whale is the biggest animal in the world
Almost the entire system of an embryo is made of cartilage, whereas that of an adult is mostly made of bones.
Fossil Fuels; Once they run out ,humans can not replacing them.
Answer: Electromagnetism
Explanation: Electromagnetism is one of the four fundamental forces (the other three are gravity, strong nuclear force and weak nuclear force.) It acts between all the particles having an electrical charge.
