When a solid dissolves in a liquid, it forms a solution, where the solid is evenly distributed within the liquid. Different types of mixtures include colloids, emulsions, and suspensions, but only solutions involve complete dissolution. Thus, the correct answer is a solution. ;
In 30 seconds, approximately 2.81 × 10^21 electrons flow through the electric device that delivers a current of 15.0 A. We calculated the total charge using the formula Q = I × t and then determined the number of electrons by dividing the charge by the charge of a single electron. This resulted in the calculation that around 2.81 × 10^21 electrons pass through the device.
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