In an oil spill, why does the oil not mix with the sea water?

In the diagram below, the northern hemisphere would be in what season at position a a.fall b. winter c.summer d.spring

This is collection of data made by comparing objects in standard units. in science, the units are metric.

What is the function of the root cap? a. extra-absorbent cells in the root cap absorb more water and nutrients b. protect the meristematic area of the stem c. contains sensors for sunlight d. increases surface area of the root