To find the circumference of a circle, you can use the formula:
\[ C = \pi \times d \]
where \(C\) is the circumference and \(d\) is the diameter.
Given that the diameter \(d\) is 3.75 kilometers and using \(\pi \approx 3.14\), we can calculate:
\[ C = 3.14 \times 3.75 \]
Now, performing the multiplication:
\[ C = 3.14 \times 3.75 = 11.775 \]
To estimate the circumference to the hundredths place, we round 11.775 to 11.78.
Therefore, the circumference of the circle is approximately 11.78 kilometers.