#4: The data is symmetric, which means it is C. NOT SKEWED
#3: Adding the outlier will not change the median, but it will decrease the mean. So the answer is B.
Answer:
volume = ⅓×π×4²×9 = 48π sq. meters
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-π/2 < arctan(x) < π/2
So cos(π/2) < cos(arctan(x)) < cos(0)
0 < cos(arctan(x)) < 1