Evidence shows that interstellar bodies are moving away from Earth, some faster than others, which BEST suggests that the universe

A) is shrinking.
B) is expanding.
C) was not formed by a big bang.
D) has always been the same size.

The correct answer here would be B) it's expanding.

answer; i believe that the correct answer is (a) potassium(k)

it is to be noted that an alpha particle is an helium nucleus. so it contains 2 protons 2 neutrons and has a mass number of 4. when alpha decay particles are ejected from the nucleus it gets transformed into an atom which has atomic number less than 2 and a mass number less than 4.

an equation that could represent alpha decay is radium 226 decay of alpha particle forms radon 222.

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