Answer: 6.45 s
Explanation:
We have the following equation:
(1)
Where:
is the height when the rock hits the ground
the height at the edge of the cilff
the initial velocity
acceleration due gravity
time
(2)
Rearranging the equation:
(3)
At this point we have a quadratic equation of the form
, and we have to use the quadratic formula if we want to find
:
(4)
Where
,
, 
Substituting the known values and choosing the positive result of the equation:
(5)
This is the time it takes to the rock to hit the ground
A physical property can be seen or a change in color.
The answer is B because you can see when wood is rotting.
It’s North of the equator
A table would be the most appropriate because that way you can compare the data.