Answer:
true.
Step-by-step explanation:
The total path covered by an object during its entire journey is called the distance covered. It is equal to the sum of all path traveled.
A person runs 21.0 km west then turns around and runs 10.0 km east. The total distance covered will be the sum of 21 km and 10 km.
d = 21 km + 10 km
d = 31 km
Hence, the given statement is true.