The answer to this is the remains and waste products of plants, animals and other living things organisms.
An adaptation that makes bipedalism possible is the need to get around. If your slithering on the ground, you could get diseases, or get hurt.
Given that Sheena's ball is a sphere, its volume can be obtained by using the formula: V_ball = (4/3)*pi*r^3, where, r is the radius of the sphere. Since the ball is 24 cm across, this means that the radius is half of the diameter which is equal to 12 cm. Thus, the volume of the ball is equal to 7238.2295 cm^2.
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