Why do i need a flu shot every year, while many other vaccinations last years or even a lifetime?

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.

What are the ingredients of oobleck?

When an object is moving away from you while still making a sound, the pitch of the sound is perceived to a. lower b. unchanged c. fluctuating d.higher