What types of elements are usually found in meteorites

It is Metals  Because it is part of a material that enters the Earth atmosphere which is the meteorites

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8

the answer is 0.42 is that is an option. this question provides no info