3。

First, the profit is 63,000 yuan.

Let x mu be used for eggplant and y for tomato.

1700 x+ 1800y = 44000《 1》

X+Y=25《2》

X= 10

Y= 15

10 * 2400+15 * 2600 = 63000 (yuan)

I'm exhausted from typing. Give me five points.