`N^(th)` level of `Li^(2+)` has the same energy as the ground state energy of the hydrogen atom. If `r_(N)` and `r_(1)` be the radius of the `N^(th)` Bohr orbit of `Li^(2+)` and first orbit radius of H atom respectively, then the ratio `(r_(N))/(r_(1))` is

Answer

3