The graph below shows the price of different numbers of towels at a store: A graph is shown. The values on the x-axis are 0, 2, 4, 6, 8, 10. The values on the y-axis are 0, 17, 34, 51, 68, and 85. Points are shown on ordered pairs 0, 0 and 2, 17 and 4, 34 and 6, 51 and 8, 68. These points are connected by a line. The label on the x-axis is Number of Towels. The title on the y-axis is Price in dollars.

Which equation can be used to determine p, the cost of t towels?

a
p = 8.50 + t

b
t = 8.50 + p

c
t = 8.50p

d
p = 8.50t