Answer:
Step-by-step explanation:
The vertical displacement function is 
, where 
is measured in meters and 
in seconds. Ball hits the ground when 
. That is:
Whose roots can be found by using the General Formula for Second-Order Polynomials:
Solutions of this polynomial are:
Only the first root is physically consistent.
The second relation is a function.
For a relation to be a function, each x-value can only have a singular corresponding y-value. Since all other relations feature x-values with multiple y-values, the second relation is a function.
Answer:
Numbers that aren't: 35 and 43. It can literally be any number.
Perfect cubes: 8,64,125,216. You can find perfect cubes by cubing any number. For example 6^3 (6 to the power of 3) is 216. A perfect cube.
