Answer:
B. Nikiya's only
Step-by-step explanation:
Mark’s cost does not vary directly with time spent talking because the cost of 0 hours is not 0 dollars
For Nikiya’s plan, the value of the constant of variation is 15
which represents Nikiya’s cost per hour
Nikiya’s only phones cost varies directly with the amount of time spent.
The correct answer is option B.
Based on the graph shown to the right, whose phone cost varies directly with the amount of time spend taking?
Nikiya’s only
Mark’s cost does not vary directly with time spent talking because the cost of 0 hours is not 0 dollars.
For Nikiya’s plan, the value of the constant of variation is 15
which represents Nikiya’s taking cost `15 dollar per hour.
[tex]slope=\frac{30-0}{2-0} =15[/tex] dollar per hour
Therefore, Nikiya’s only phones cost varies directly with the amount of time spent.
For more information:
https://brainly.com/question/21606425
