An aquifer is water stored in the _.

A. zone of saturation

B. zone of impermeability

C. zone of aeration

D. Zone of porosity

People keep spending additional units of a particular resource on a want until their marginal benefit is  decreasing withgreater thanless thannot affected by  their marginal cost.

In a command economy, the majority of goods and services are provided by the

Agriculture is a. slowly being replaced by mining as the primary industry in southern africa c. not possible in southern africa because of drought b. the primary industry in southern africa d. none of the above