To find the constant of variation \( k \), we can use the formula for direct variation:
\[ y = kx \]
Where:
- \( y \) is the total cost (in this case, $48.77),
- \( x \) is the number of gallons purchased (in this case, 14.5 gallons),
- \( k \) is the constant of variation.
We can rearrange the equation to solve for \( k \):
\[ k = \frac{y}{x} \]
Substituting the values:
\[ k = \frac{48.77}{14.5} \]
Now, performing the calculation:
\[ k \approx 3.36 \]
So, the constant of variation \( k \) is approximately 3.36.
The correct response is:
k=3.36.