Figure 11: Residual (in terms of ) due to change in initial values of the raw material (, ). (a) Residual (in terms of ) due to 25% increase in the initial values of the raw material (, ). (b) Residual (in terms of ) due to 30% decrease in the initial values of the raw material (, ). (c) Residual (in terms of ) due to 20% decrease in the initial values of the raw material (, ). (d) Residual (in terms of ) due to 10% decrease in the initial values of the raw material (, ).