Given a sphere with a diameter of 8 cm, find its volume to the nearest whole number. A 85 cm^3
B. 2144 cm^3
c. 201 cm^3
D. 268 cm^3

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.

which expression represents the approximate length of bc?

step-by-step explanation:

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