Black surfaces is you'r answer. or dark mater. ya those are you'r answer.
D. Gravitational potential
I think it's C. if we're talking about a rover.
But if it's a rocket that's computerized and automatic (synonym of unmanned)... Then it's B.
Displacement is usually given to you as it is, but you can also get displacement through velocity by Δd= Δv*t, where <span>Δv is the change in velocity and t is the change in time.
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