1. Study the COMMON construct of FORTRAN, and discuss the difference between labeled and unlabeled COM140m, as well as their possible use. Also, discuss the mechanisms pro-vided by FORTRAN to initialize COMMON areas. 2. Describe how to use C to define a common area for storing data. Do the same for Pascal. 3. We have criticized the POP_2 interface to the stack of on the grounds of being too specialized. We said that if we generalize the interface to POP, clients have more flexibility in its use. Specialization, however, is sometimes necessary for reasons of efficiency. For example, consider a stack that is implemented on one node of a distributed system. Compare POP and POP_2 in terms of efficiency of the interface for clients.