Answer:
17.6 mi
Explanation:
I know you are using Windows 10 OS or something because of the cortana thingie and task bar option, and you can do Windows Key + Shift + S to take a screenshot.
This gives much better quality than a third party device and lets us evade the terrible pixel green line rippley thingies that form. Plus it is more efficient and faster.
Circumference formula is Diameter * Pi.
I assume the 5.6 mi. is the diameter since the line segment is going completely through the circle.
Pi is something of the lines of 3.141592653 blah blah blah and goes on forever, but the point is, we take it to be 3.14 when doing circle stuff so we don't die from old age trying to figure out a question of a 1 x 1 circle.
So 5.6 * 3.14 is 17.584 which is your answer.
It says to round to the nearest tenth though, so you round and get
17.6 since the 5 in 17.584 is the tenths place, the 8 is the hundredths place, the 4 is the thousandths place and so on and so forth.
(The " * " symbol represents multiplication and is in use all the time when going to higher levels of education.)