What is the value of human life from an economics perspective?

Use the Shih & Halpern article, and Emanuel, Fuchs & Garber's "Essential elements. . . " article beginning p.33 in the "Fuch's Manuscipts" document to answer the following:

What is the value of human life? Health economists have used several approaches to attempt to answer that question. But why – isn’t the value of human life immeasurable? Discuss the role of cost-benefit analysis and the related concepts of cost-effectiveness analysis, cost-utility analysis, QALYs and DALYs in answering this question. Is valuing human life different than valuing quality of life achieved through a health intervention?