The ratio (R) of output resistance r _ 0 , and the input resistance...

The input resistance ${r}_{i}$ of a transistor is in the range of $1 - 10kΩ$.

The output resistance ${r}_{0}$ of a transistor is in the order of $100kΩ$.

So, the ratio of output resistance and input resistance,

$R = \dfrac{{r}_{0}}{{r}_{i}} = \dfrac{100kΩ}{\left(1 - 10\right)kΩ}$

$⇒ R ~ {10}^{2} - {10}^{3}$