Which one of the following is the correct quantity of zinc sulphate required to prepare 100 litres of 200 ppm solution for foliar spray? Quantity of zinc sulphate required (in grams)

To calculate the quantity of zinc sulphate required, we use the formula:
Quantity (in grams) = Concentration (in ppm) × Volume (in liters) ÷ 1000

Given that the concentration is 200 ppm and the volume is 100 liters, we can calculate:
Quantity (in grams) = 200 ppm × 100 liters ÷ 1000 = 20 grams

Therefore, the correct answer is:
D. 20 grams