Time Since Starting to Walk (seconds) 3 6 9 12 15 Total Distance Walked (feet) 12 24 36 ? 60

Melanie is walking at a constant speed. The total distance she walked at various times since she started is shown in the table.

Question:

A. After 3 seconds, what is the ratio of the total distance Melanie has walked in feet to the time she has been walking in seconds?

B. Plot the points from the table on a coordinate plane. Is the ratio of the total distance Melanie has walked in feet to the time she has been walking in seconds always the same, or does it vary? Justify your answer.

C. What is the missing value in the table, and why?

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