. If a scientific experiment repeatedly gives the same results, the experiment is
being done by an untrained student
reliable
invalid
a law

Second option

Explanation:

If a scientific experiment is repeatedly giving you the same results that would mean that the results are precise and are very "reliable" for your conclusion which means your answer is the second option. During a experiment you are suppose to repeat the steps at least three times to make sure your results are reliable, doing so and it giving you the same results each trial just means that the results itself are very reliable.

Hope this helps.

because of

the most common energy conversion is from kinetic energy to potential energy, and then from potential energy to kinetic energy.

later on comes the heat energy, mechanical energy, and other energy conversions.

this energy conversion is so common that we can find it in our day to day lives as well.

- one of the most common energy conversions involves the changing of potential energy to kinetic energy or kinetic energy to potential energy