<math>a_0 = {{4\pi\epsilon_0\hbar^2}\over{m_e e^2}}</math>
where:
It has a value of 5.29189379×10-11 m, or about half an angstrom.
... per capita income for the town is $25,466. 7.0% of the population and 4.6% of families are below the poverty line. Out of the total people living in poverty, 7.1% are ...