$10$ kg of water at $300$ K is poured into a bucket containing $10$ kg of water at $350$ K . Heat capacity of water is $4.2 \mathrm{~kJ} / \mathrm{kg}$. K . Neglecting any heat losses to the surroundings, the change in the entropy (in $\mathrm{kJ} / \mathrm{K}$ ) of the system during this process $\text{(rounded off to two decimal places)}$ is _________.
- $0.00$
- $0.25$
- $0.50$
- $0.75$
