You need to observe the car at two different times.
-- The first time:
You write down the car's speed, and the direction it's pointing.
-- The second time:
You write down the car's speed and the direction it's pointing, again.
You take the data back to your lab to analyze it.
-- You compare the first and second speed. If they're different,
then the car had acceleration during the time between the two
observations.
-- You compare the first and second direction. If those are different,
even if the speeds are the same, then the car had acceleration during
the time between the two observations.
(Remember, "acceleration" doesn't mean "speeding up".
It means any change in speed or direction of motion.)
Answer:
An object responds to a force by tending to move in the direction of that force
Explanation:
The inertia of a body can be defined with the help of Newton's second law
F = m a
Where F is the applied force, a is the acceleration of the body and m is the mass
the force and the acceleration are vectors that point in the same direction and m is a scalar constant that relates the two vectors, this scalar constant is called masses and it measures the resistance of the bodies to the change of motion.
From the previous statement we see that the statement that best describes inertia is:
An object responds to force by tending to move in the direction of the force.
Gravitational force is given by, 
Where, m and M are the masses of the objects, R is the distance between them and G gravitational constant.
Gravitational force of the star on planet 1, 
Gravitational force of the star on planet 2, 
Ratio, 
Therefore, the gravitational force of the star on the planet 1 is three times that on planet 2.
'Pressure' is (force) / (area).
The only choice with those units is #1 .
