List the objectives of aspen plus process simulator. (b) what are the basic equations that are solved in aspen plus? (no need of mathematical forms)? (c) what is the difference between 'equation oriented' and 'sequential modular' solution method? (d) write down a few common equation of state models (at least 4) used in aspen? (e) what are the different types of connections in aspen to join various equipment and units?