Water.
Sound travels slowly because the amount of pressure.
Answer:
False.
Explanation:
I am almost entirely sure that DNA testing had not been discovered at this time, but regardless of whether that is true, the very first criminal case that DNA testing was used in occurred in 1985. So no, it was not used commonly in the 20's.
Answer:
Hey there.
<em><u>There are three types of scientific investigations: descriptive, comparative, and experimental scenitific investigations.
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<em><u></u></em>
fist we have <em><u>Descriptive</u></em> scientific investigations.
Descriptive investigations use careful observations and measurements to develop findings.
Then we have <em><u>
comparative </u></em>Investigation.
comparative investigations Involve collecting data on different populations/organisms, under different conditions (Times of year, locations), to make a comparison. for Example, Using a hand lens to examine the color and texture of four different rocks.
Lastly we have <em><u>experimental</u></em> scientific investigations.
Experimental investigations involve a process in which a "fair test" is designed and variables are actively manipulated, controlled,
I hope it helped!!!
<em>Wbob1314</em>