Neco 2023 Agricultural Science Question 26

A farmer harvests 500\,kg of fresh cassava roots with an initial moisture content of \(60\%\) (wet basis). He can process the roots by either:\n(A) Sun‑dry for 48\,h, which reduces the moisture to \(20\%\) (wet basis), then finish drying in a mechanical dryer that removes moisture at a constant rate of \(5\ \text{kg h}^{-1}\) until the moisture reaches \(12\%\) (wet basis).\n(B) Directly use the mechanical dryer for 10\,h, where the moisture‑removal rate declines linearly from \(8\ \text{kg h}^{-1}\) at the start to \(4\ \text{kg h}^{-1}\) at the end.\nThe dryer consumes \(0.5\ \text{kWh kg}^{-1}\) of electricity per kilogram of water removed. Determine which option gives the lower final moisture content and calculate the total electricity consumed for that option.