not b, as sound cant travel in a vacuum (like outer space)
The size and shape have no effect on density of matter because the size and shape of the particles stay the same no matter what.
Elements emit colours when heated because electrons in atoms can have only certain allowed energies.Heating an atom excites its electrons and they jump to higher energy levels. When the electrons return to lower energy levels, they emit energy in the form of light. Every element has a different number of electrons and a different set of energy levels. Thus, each element emits its own set of colours. See, for example, mercury and neon above. Those colours are as distinctive to each element as fingerprints are to people.
The Europeans strolled into the new land of America and used their technology and strength by numbers to take over the Indians world. The iron edge blades and the gunpowder-powered guns were to much for any <span>Indian and the Europeans would often capture the king of a certain community and take over the</span>
