Answer:
Constant of proportionality = 1.25
Equation: y = 1.5x
Table:
Cups Price
8 $10
10 $12.5
12 $15
14 $17.5
Step-by-step explanation:
Option 3 says that Micah sold 8 cups of hot cocoa for $10.
First, we need to identify the constant of proportionality. This constant can be calculated as the division of the price by the number of cups, so the constant of proportionality k is equal to:

The constant of proportionality tells us the price per unit.
Then, we can write the equation that describes a proportional relationship as:
y = kx
Where k is the constant of proportionality, x is the number of cups and y is the price. So, the equation or rule is:
y = 1.25x
Now, we can fill the table using the equation as follows:
Cups Price
8 1.25(8) = $10
10 1.25(10) = $12.5
12 1.25(12) = $15
14 1.25(14) = $17.5
Finally, we can make the graph as follows: