Why was the chernobyl radiation was used in Ukraine?

The picture represents the process that produces most of the energy used by living organisms on earth. which process is represented in the picture? a) the magnetic attraction between two hydrogen nuclei. b) the fusion of hydrogen nuclei to produce a helium nucleus in the core of the sun. c) the fission of hydrogen nuclei to produce a helium nucleus in the core of the sun. d) the chemical reaction between hydrogen nuclei to produce a helium nucleus in earth's atmosphere.

How many neutrons does an element have if its atomic number is 50 and its mass number is 166

Why is it that 85.48 rounded to two significant figures is 85 and not 86?