¡Hola!
For this problem, first, lets recabe information:
v = 0 m/s
t = 3 s
g = 9,82 m/s²
v' = ?
d = ?
First, for calculate the final velocity:
v' = v + g * t
v' = 0 m/s + 9,82 m/s² * 3 s
v' = 29,46 m/s 
Now, for calculate how far did it fall:
d = v * t + g * t^2 / 2
Like v = 0 m/s, we can simplificate equation:
d = g * t^2 / 2
d = 9,82 m/s² * (3 s)^2 / 2
d = 9,82 m/s² * 9 s² / 2
d = 88,38 m / 2
d = 44.19 m 
¡Buena suerte!
The focal length of a magnifying glass is the distance between the focal point and optical centre of the magnifying glass.
<h3>Focal length</h3>
The focal length, f is the distance from a lens or mirror to the focal point, F.
This is the distance from a lens or mirror at which parallel light rays will meet for a converging lens or mirror or appear to diverge from for a diverging lens or mirror.
A magnifying glass is a converging lens which produces a enlarged, erect and virtual image when an object is placed between the focal point and optical centre.
A magnifying glass will bring to focus at a point sun rays which can cause the paper to catch fire if it is held in place for long.
This point at which the most concentrated ray of light is shining on the paper, is the focal point for that magnifying glass.
Therefore, the focal length of a magnifying glass is the distance between the focal point and optical centre of the magnifying glass.
Learn more about about focal length at: brainly.com/question/25779311
Answer:
An unbalanced force means that there are more than one forces with different directions or magnitudes affecting the object. In this case, the vector addition of the forces should be done. The vector addition will result a net force. The object will move in the direction of the net force.
That would be a nebula, which is an interstellar cloud of hydrogen gas, dust, and plasma. It is the first stage of a star's cycle.
