Krishna distributed $10$ acres of land to Gopal and Ram who paid him the total amount in the ratio $2:3$. Gopal invested a further Rs.$2$ lakh in the land and planted coconut and lemon trees in the ratio $5:1$ on equal area of land. There were a total of $100$ lemon trees. The cost of one coconut was Rs.$5$. The crop took $7$ years to mature and when the crop was reaped in $1997$, the total revenue generated was $25$% of the total amount put in by Gopal and Ram together. The revenue generated from the coconut and lemon trees was in the ratio $3:2$ and it was shared equally by Gopal and Ram as the initial amount spent by them were equal.

What was the ratio of yields per acre of land for coconuts & lemons?