Which device is used to maintain the mixture of pesticide in a solution within the spray tank?

The device that maintains the mixture of pesticide in a solution within the spray tank is the agitator. An agitator is essential because it ensures that the pesticide remains evenly mixed with the carrier solution (e.g., water or oil) in the tank. This homogeneous mixture is critical for effective application since uneven distribution can lead to areas of over-application or under-application on the target surface.

An agitator can be mechanical, such as a propeller or paddle, or it can operate through hydraulic means, depending on the design of the spray tank. Its primary function is to keep the particles in suspension, preventing settling that could occur if the solution were left undisturbed. This consistency in the mixture is key to achieving the desired performance of the pesticide.

The other devices mentioned serve different purposes: a sprayer is the apparatus used to apply the mixture, a filter helps to remove impurities before they enter the sprayer, and a metering system controls the amount of pesticide added to the solution but does not maintain its consistency once mixed.