Plants have cell walls, but animals do not because otherwise we wouldn't be able to move.
Hardness, color , and luster.
But since you can pick one, I would say hardness
209 km/h = 58.0 m/s
2as = v² - u²
Assuming the ball started from rest,
a = (58)² / 2 x 0.11
a = 15,290 m/s²
Okay, haven't done physics in years, let's see if I remember this.
So Coulomb's Law states that

so if we double the charge on

and double the distance to

we plug these into the equation to find
<span>

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So we see the new force is exactly 1/2 of the old force so your answer should be

if I can remember my physics correctly.