Final answer:
A cost-benefit analysis can determine whether a detailed economic feasibility study is justified, considering factors like environmental impact.
Step-by-step explanation:
A detailed economic feasibility study can be justified by conducting a cost-benefit analysis. This analysis involves comparing the costs and benefits of a project or investment to determine its viability.
For example, in the context of pipeline construction, an economist would consider not only the marginal benefits resulting from the construction but also the potential marginal costs and external costs. Tools like environmental impact assessments and pre-feasibility studies may also be used to evaluate the environmental impact and feasibility of the project.
By conducting a cost-benefit analysis and considering factors like environmental impact, the economist can determine whether a detailed economic feasibility study is justified.