Answer:
climatic changes
ambient changes
human interferance and the growt of cities and human civilization
and invasive especies
Explanation:
The angle of refraction is <span>45°.</span>
The sign associated with the average velocity of the object is negative.
<h3>
Average velocity of the object</h3>
The average velocity of the object is calculated as follows;
Average velocity = (v1 + v2)/2
v1 = -20/30 = -0.667 m/s
v2 = 20/50 = 0.4 m/s
Average velocity = (-0.667 + 0.4)/2
Average velocity = -0.134 m/s
Thus, the sign associated with the average velocity of the object is negative.
Learn more about average velocity here: brainly.com/question/6504879
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The longer the lever the longer the power
