I need some one to hang with

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

air

in a tire you fill a tire with air

then a couple days later you check the air pressure in the tire

hope this mark me brainliest