Question 3
when completing a scientific investigation, you will know your results are reliable when you are able to
duplicate your results
communicate your results
evaluate your results.

Explanation:

A scientific investigation refers to researches where we apply the scientific method, which is characterized by involving systematic observations, measurements, experimentation, analysis, system of hypothesis, and other elements.

Basically, when we have a hypothesis, we try to prove it developing a scientific investigation which must be defined with the relation between a dependent variable and an independent variable. So, through systematic observations, we study the relation between these variables, experimenting and analysing all results we get from those observations.

So, one important characteristic of scientific investigation is research reliability, which is the degree to which a research produces consistent results, and one ingredient to obtain that it's the posibility of reproducing the results, that is, duplicating them in other contexts. For example, if we study Newton's second law, you will be able to reproduce the results of such law in different contexts.

Therefore, the right answer is "duplicate your results".

a.) travels faster in solids because the particles are closer together.

air is a gas water is a liquid

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

hope this ! : )