The best option is the first one (Six yards of rope costs $5.50). It is the lowest unit cost.
<u>Step-by-step explanation:</u>
For the given question case, first we should compare the unit costs of the choices provided and evaluate the best option.
Choice 1:
Six yards of rope costs $ 5.50

Choice 2:
Four yards costs $ 4.75

Thus, the best choice is the first one. Because it is the lowest unit cost.
Answer:
Range of F(x) = (-∞ ,72).
Step-by-step explanation:
Range of the function F(x) means the set of values which are taken by the function along its domain.
F(x) = 72 - 
Since coefficient of
is negative on the right side ,
Maximum value of F(x) will come at x = 0.
Which is, F(0) = 72.
Now, as x increases , F(x) decreases , when x will reach infinity ,
F(x) will be reaching negative of infinity .
Thus, F(x) is ranging from -∞ to 72 .
Range of F(x) = (-∞ ,72).