9. Baking soda is added to a beaker of vinegar. Which statement is an inference? A. Bubbles are forming.
B. A fizzing sound is made.
C. The vinegar is becoming cloudy.
D. A chemical reaction is taking place.

the earth is thought to have been formed about 4.6 billion years ago by collisions from a cloud of hydrogen, helium, rock, ice and other materials. these were pulled together by gravity to form objects in and around earth like- asteroids and small early planets called planetesimals.

so, the best possible answer to this question will be option d- to harden materials to form different parts of earth’s layers