Refers to an object positioned in the back of something or somebody ?

The earth remains in orbit around the sun due to the force of gravity. how does the force of gravity exerted by the sun on the earth compare to the force of gravity exerted by the earth on the sun?

Apebble is thrown into a calm lake, ripples are formed from the center and move outward. the water particles in the lake travel in a circular pattern that moves up and down on the surface of a lake, and the energy travels a) diagonally. b) downward. c) horizontally. d) upward.

Un conductor circula por una carretera en una velocidad de 90 km/h y b que se enciende la luz amarilla de un semáforo situado una distancia de 150 m. si el semáforo tarda tres segundos en cambiar a rojo el coche frena con una aceleración de 2 m por segundos 2¿ cometer una infracción ese conductor?