In order to calculate the time taken by the snowball to reach the highest point in its journey, we need to consider the variables along the y-direction.
Let us list out what we know from the question so that we can decide on the equation to be used.
We know that Initial Y Velocity
= 8.4 m/s
Acceleration in the Y direction 
= -9.8 m/
, since the acceleration due to gravity points in the downward direction.
Final Y Velocity 
= 0 because at the highest point in its path, an object comes to rest momentarily before falling down.
Time taken t = ?
From the list above, it is easy to see that the equation that best suits our purpose here is 
Plugging in the numbers, we get 0 = 8.4 - (9.8)t
Solving for t, we get t = 0.857 s
Therefore, the snowball takes 0.86 seconds to reach its highest point.
<u>Answer:</u>
The correct answer option is D. The distance between the planet and the Sun changes as the planet orbits the sun.
<u>Explanation:</u>
Kepler’s laws of planetary motion, derived by the German astronomer Johannes Kepler, are the laws of physics that describe the motions of the planets in the solar system.
According to the Kepler's first law of planetary motion: the path on which the planets orbit around the sun is elliptical in shape, with the center of the sun at one focus.
Therefore, the distance between the Sun and the planets vary as the planet orbit around the sun.
