The total exports and revenues from the exports of a country are given in the two charts shown below. The pie chart for exports shows the quantity of each item exported as a percentage of the total quantity of exports. The pie chart for the revenues shows the percentage of the total revenue generated through export of each item. The total quantity of exports of all the items is $500$ thousand tonnes and the total revenues are $250$ crore rupees. Which item among the following has generated the maximum revenue per $kg$?

1. Item $2$
2. Item $3$
3. Item $6$
4. Item $5$