The distance decreases as the time increases
The gravitional potential energy, relative to the bottom of the giant drop, in joules, is (9800) times (the height of the drop in meters).
That's the PE of the empty car only, not counting any hapless screaming souls who may be trapped in it at that moment.
Kepler's 3rd law is given as
P² = kA³
where
P = period, days
A = semimajor axis, AU
k = constant
Given:
P = 687 days
A = 1.52 AU
Therefore
k = P²/A³ = 687²/1.52³ = 1.3439 x 10⁵ days²/AU³
Answer: 1.3439 x 10⁵ (days²/AU³)
The slope of a speed-time graph is the acceleration represented by the graph.
All other parts of this question refer to a lab experiment or exercise
where I was not present, but Zeesam16 was. Therefore I have no data
with which to answer the rest of the question, and hope that Zeesam can
handle it.
You get the net force acting on it ... the sum of the strengths and directions
of all the individual forces there may be.