In the stiffness matrix method of analysis, the values of displacements in {D} necessary to ensure the equilibrium of the joints are determined using which of the following relations? (where {D} = displacement vector, [K] = stiffness matrix, and {P} = load vector)

In the flexibility matrix method of structural analysis, the values of redundant forces necessary to ensure geometric continuity of the structure are determined by using which relation? (where {Dp} = displacement at release due to applied loading, [F] = flexibility matrix, and {XR} = redundant forces on the released structure)