1 hectare = 10,000 square meters Area of the farmland = 100 m x 500 m = 50,000 square meters Now, we can convert the area to hectares: Area in hectares = 50,000 square meters / 10,000 square meters/hectare = 5 hectares Next, we can calculate the quantity of cowpea seeds required using the given seed rate: Seed rate = 25 kg/hectare Quantity of cowpea seeds required = Seed rate x Area Quantity of cowpea seeds required = 25 kg/hectare x 5 hectares Quantity of cowpea seeds required = 125 kg Therefore, the quantity of cowpea seeds required to cultivate the farmland is 125 kg. The correct answer is "125 kg."