What formula is used to calculate the pounds of material required for a desired concentration?

The correct formula for calculating the pounds of material required for a desired concentration is based on the relationship between parts per million (ppm), the area to be treated, and the concentration of the product being used. Option B provides the formula that accurately captures this relationship by multiplying the pounds of material (with a specific weight per acre) by the desired concentration in ppm and the area in acres.

To understand why this value is used, it's important to recognize that different chemicals have different rates at which they provide effective concentration levels. The figure of 2.7 pounds corresponds well to typical values used in many aquatic pest control applications where the calculation needs to factor in both the desired concentration in the water body and the volume of water to achieve the expected control of pests.

In practice, applying this formula allows for precise applications that ensure effectiveness while minimizing excess product use, which is critical for environmental protection and regulatory compliance. Thus, when planning an aquatic pest control treatment, using this formula with the appropriate parameters correctly guides the application rate.