North african countries that have arid climates

The solstices and equinoxes, and the number of hours of daylight associated with each, are major factors in the seasons. use the drop-down menus to identify the month when each of these events occurs. the winter solstice in the northern hemisphere: an equinox in both hemispheres: the summer solstice in the northern hemisphere:

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.

Which of the following is the main purpose of using an anchored network of booms which funnel debris to a collection area?