Semiconductor Devices And Logic Gates

$\beta \frac{r}{R_L}, \beta^2 \frac{r}{R_L}$

$\beta \frac{\mathrm{r}}{\mathrm{R}_{\mathrm{L}}}, \beta\left(\frac{\mathrm{r}}{\mathrm{R}_{\mathrm{L}}}\right)^2$

$\beta \frac{R_L}{r}, \beta^2 \frac{R_L}{r}$

$\beta \frac{R_L}{r}, \beta\left(\frac{R_L}{r}\right)^2$