This question can be solved by using equations of motion.
A. The grapefruit dropped by "3.1 m".
B. The speed of the grapefruit, when it hit the ground was "7.8 m/s".
A.
We will use the second equation of motion here to find out the distance dropped by the grapefruit:
[tex]h = v_it+\frac{1}{2}gt^2[/tex]
where,
h = height dropped = ?
vi = initial speed = 0 m/s
t = time period = 0.8 s
g = acceleration due to gravity = 9.81 m/s²
Therefore,
[tex]h = (0\ m/s)(0.8\ s)+\frac{1}{2}(9.81\ m/s^2)(0.8\ s)^2[/tex]
h = 3.1 m
B.
Now, we will use the first equation of motion to find out the final speed:
[tex]v_f = v_i +gt[/tex]
vf = 0 m/s + (9.81 m/s²)(0.8 s)
vf = 7.8 m/s
Learn more about equations of motion here:
https://brainly.com/question/20594939?referrer=searchResults
The attached picture shows the equations of motion in the horizontal and vertical directions.
