If "u" varies directly with "v" and u = 6 when v = 7, what is "u" when v = 4?

What are potential hypotheses (explanations) regarding why there are ecological equivalents between many metatherians and eutherians? discuss your hypothesis in terms of the processes that could lead to the current ecologies and distributions of metatherians and eutherians.

The area of a circle is equal to 1 dm². find the radius of the circle.

Which equation can be used to measure the density of water in a spherical water tank? let w represent the number of water particles within the region.