long answer is required for this

Q.1. (a) Describe three factors which can affect drug stability. Suggest how an accelerated stability programme might incorporate such factors in seeking to detect potential drug product instability for an inhalable drug product. (b) Describe the design of a bracketing approach to implementing a stability testing programme. (c) When formulating a dispersion of a solid in a liquid, the formulator's goal will be to slow down sedimentation and improve redispersibility. Account for this objective and indicate the reasons why this difficult formulation pathway is sometimes chosen