twenty (20)
In the Rb atom, the electron configuration is [Kr]5s^1. This means there is 1 electron in the 5s sublevel of the Rb atom.
21 5s
Five thousand, five hundred respectively.
All the multiples of 10.
There are one hundred, hundred millions in one billion.
24
10
20
90
There is only one hundred thousand in a hundred thousand.
i think there are 18 digit 5s.
One hundred million.