Since the farmer if of the shape of parallelogram, its area is given by:
[tex] Area = b*h [/tex]
where b is base and h is height of parallelogram.
Base = 4.25 km
and Height = 3.5 km
Plugging the values in the formula to find the area,
[tex] Area = 4.25 * 3.5 [/tex]
Area =14.875 square km
Answer : Area of the farm is 14.785 square kilometers.