Answer the question based on the following information.
Rajiv reaches city B from city A in $4$ hours, driving at speed of $35 \; \text{kmph}$ for the first two hour and at $45 \; \text{kmph}$ for the next two hours. Aditi follows the same route, but drives at three different speeds: $30, 40$ and $50 \; \text{kmph},$ covering an equal distance in each speed segment. The two cars are similar with petrol consumption characteristics $\text{(km per litre)}$ shown in the figure below.
Zoheb would like to drive Aditi’s car over the same route from A to B and minimize the petrol consumption for the trip. What is the quantity of petrol required by him?
- $6.67 \; \text{litre}$
- $7 \; \text{litre}$
- $6.33 \; \text{litre}$
- $6.0 \; \text{litre}$