Your answer would be the last option, c = √(E/m).
We can see this when we rearrange the equation, as:
E = mc²
÷ m
E/m = c²
√
√(E/m) = c
So you got all the steps in rearranging correct :)
I hope this helps!
<h3>
Answer: 120 degrees</h3>
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Work Shown:
n = number of sides = 6
i = measure of interior angle
i = 180(n-2)/n
i = 180(6-2)/6
i = 180(4)/6
i = 720/6
i = 120
Each interior angle of this regular hexagon is 120 degrees.
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Alternative Approach:
E = exterior angle
E = 360/n
E = 360/6
E = 60
Each exterior angle of this regular hexagon is 60 degrees
i+E = 180
i = 180-E
i = 180-60
i = 120
We get the same answer.