Cuando una sustancia cualquiera, no sufre un cambio que altera su composición, y sus propiedades, este cambio puede clasidicarse como: a)fisico b)natural c)quimico d)de estado

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.

conduction, convection, radiation

the answer is a. hope this .