Mr. Roentgen's x-rays allowed scientists to measure the size of the atom. The x-rays were small enough to discern the atomic clouds. This was done by scattering x-rays from atoms and measuring their size just as Rutherford had done earlier by hitting atoms with other nuclei starting with alpha particles.
a/b. The ball has velocity vector at time 
where 
is the ball's initial speed and 
.
c. At its highest point, the ball has 0 vertical speed. This occurs when
d. Recall that
so that at its highest point,
e. This is just twice the time it takes for the ball to reach its maximum height, 
.
f. The ball's horizontal position after time is
so that after the time found in part (f), the ball has traveled
There are asteroids, which are rocks that fly through the space, and meteors which are pretty much the same. The only difference is their sizes. There are also planets, big and small. The moon, the dwarf planet Pluto, and many more. There are probably thousands of other planets that we haven't quite yet discovered. Soon we will though. There are also billions of stars, such as the sun, and some others we don't have names for that form constellations.
Hope this helped!!
Answer:
The magnitude of their velocities will be the same but their direction will be reversed.
