In longitudinal waves the places where the coils are bunched together are called *

convex lenses are thicker at the middle. rays of light that pass through the lens are brought closer together (they converge). a convex lens is a converging lens. when parallel rays of light pass through a convex lens the refracted rays converge at one point called the principal focus.

c because the action was the roller coaster reaches bottom of hill (action) reaction would be blood tends to drain away from head

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