Answer:
Explanation:
Remark
We have to assume something about the question. When he runs around the semicircle, does that include the diameter. I'm going to say yes, but it may not be so.
Given
d = 2*r + 2*pi * r/2
r = 10 meters
Solution
d = 2 * 10 + 2* 3.14 * 10/2
d = 20 + 31.4
d = 51.4
Answer
The distance is 51.4
The displacement is zero. Why zero? Because you going around the track once and you wind up exactly where you started from.
