Why carbon nano tube is being studied? Where is its application? How does SWCT and MWCT differ with regard to load carrying mechanism? Does it have, presently, any real / probable applications? What type of problems cannot be explained by the theories at the micro level for which a further deeper study is required (except for those for which AFM study has to be used)? Does the continuum mechanics theory remain valid even at nano level, especially for compressible fluid flow?