To determine which pair exclusively consists of herbicides, we must analyze each option based on the properties and uses of the chemicals listed.
Thus, the correct answer is: Sodium chlorate and sodiumarsinite, as both chemicals are herbicides.
Method used for separation of mixture of products (B and C) obtained in the following reaction is: 
Two circular discs of radius \(10\) cm each are joined at their centres by a rod, as shown in the figure. The length of the rod is \(30\) cm and its mass is \(600\) g. The mass of each disc is also \(600\) g. If the applied torque between the two discs is \(43\times10^{-7}\) dyne·cm, then the angular acceleration of the system about the given axis \(AB\) is ________ rad s\(^{-2}\).
