The cost of fencing a rectangular plot is $ \text{₹} \; 200 \; \text{per ft}$ along one side, and $ \text{₹} \; 100 \; \text{per ft}$ along the three other sides. If the area of the rectangular plot is $60000 \; \text{sq. ft},$ then the lowest possible cost of fencing all four sides, in $\text{INR},$ is

- $160000$
- $100000$
- $120000$
- $90000$