Build the algebras shown in Figure 5.46(b), which completes Figure 5.46(a). Notice that equality has different meanings in different algebras. For instance, multisets are sets with possible repetitions of elements, but in which the order is not relevant. Thus, {a, b, a, c} = {b, a, c, a) {a, b, b, c }. Sets are considered a specialization of multisets, because they can be obtained by adding more equations to the equations for equality between multisets.