For a diffusional transformation $\text{(i.e., growth of $\beta$ precipitates in an $\alpha$ matrix)}$, which of the following is/are true with increasing degree of undercooling?
- Rate of transformation first increases and then decreases
- Rate of transformation first decreases and then increases
- Thermodynamic driving force increases monotonically
- Mobility of atoms in $\alpha$ matrix remains unchanged
