A farmer uses urea fertilizer to increase yield in their wheat field. If they do not apply any urea, they receive a yield of 2.5 tons per hectare. From past experiences, they find out that for every bag of urea, the yield increases by 0.2 tons per hectare.

a. 4 tons per hectare
b. 3 tons per hectare
c. 5 tons per hectare
d. 2 tons per hectare