(a) Provide an example of where inter-industry competition is an important source of competition for a firm. (b) Provide an example of where foreign competition is an important source of competition for a firm. (c) Provide an example of where contestable markets competition is an important source of competition for a firm. (d) Explain why an increase in competition usually helps improve market conditions in the U.S. economy. (e) Does the U.S. government have a responsibility to maintain competitive markets? Explain.