According to Newton's law of motion, when we shake a mango tree, mangoes fall down explain.​

When we shake a mango tree, the mangoes fall down. It is because when we shake the tree, the mango tend to be rest due to inertia where as the branches are in motion. That is why the mangoes tend to be at rest due to inertia where as the branches are in the motion.

Answer (d) the universe had cooled enough for atoms to combine, protons and neutrons were too far apart to form nuclei;