Using a linear function, it is found that the slope of the problem is of $70.
A linear function for a cost is modeled by:
[tex]C(t) = C(0) + at[/tex]
in which:
Verizon charges a $100 initial contract fee, then $70 a month for a basic cell phone plan, then:
[tex]C(t) = 100 + 70t[/tex]
Then, the slope of the problem is of $70.
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