How are sand dunes and deltas similar?

a. they are both formed by erosion.
b. they are both formed by weathering.
c. they both can be prevented by contour plowing.
d. they both have poor quality soil not suited for farming.

The energy needs of a human population are not affected by

Which sequence correctly shows the path of carbon dioxide during repiration?

Which of the following is a consequence of urban heat islands? increased precipitation downwind of the city? increased precipitation upwind of the city? decreased winds within the city? increased winds within the city?