Describe the term "semi-permeable" (or "selectively-permeable) membrane. Why is it important?

Why is earth's outer core hotter than earth’s oceanic crust? earth’s oceanic crust is denser than earth’s outer core is. earth’s oceanic crust has lava flowing from the mantle. earth’s outer core has a composition of solid iron and nickel. earth’s outer core is deeper within earth than oceanic crust is.

The “ecological footprint” left by a citizen of a developed nation is about four times larger than that left by a citizen of a developing nation. why is this the case?

The basic kind of life cycle found in the simplest animals is: haplontic or diplontic