Solar: rays from the sun shine on solar pannels creating energy which is a renewable energy.
Water: water stored at a dam flows through turbines creating energy which is a renewable energy
Fossil fuels: fossil fuels are extracted from the ground the burned to create energy and this is a nonrenewable resource.
Hope this helps :)
Answer:
All elements in the same group of the periodic table have the same number of valence electrons. This made it possible to compare the valence of the alien elements to the valence of elements from our periodic table, and match the alien elements to the correct group. For example, our group 14 elements all have 4 valence electrons, so the alien element with 4 valence electrons had to be part of group 14 also.
If it’s chemistry then In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent.