spm mid questions

1.what is waterfall model . what are the disadvantages in waterfall model
2.explain about the different parameters included in improving software economies
3.what are the principles of the model software management
4.explain abt the life cycle phases in detail
5.(A) what is artifact set
   (B)explain abt management set artifact
6.exlain abt evolution of artifact on the different life cycle phases
7.what is workflow explain about seven workflow
8.write abt predominent cost elimination process