Elements are substances made of only one type of atom is true,
<span>another limitation is the span of the human life. assuming that you want to go outside of the solar system, it is much too far to travel for a human.
in addition there is the speed limitation. of course, Einstein predicts that in order to travel at the speed of light, the substance must have no mass. therefore, it is impossible for a human - let alone a spaceship - to travel at that speed, crushing our dreams of interstellar travel (in a human lifespan).
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Answer: A dune is a mound of sand formed by the wind, usually along the beach or in a desert. Dunes can also be formed by strong currents beneath the water.
Hello there! A proton has a positive charge of (+1) and has a lesser mass compared to a neutron! Hope this helps! Have a great day!