13. A natural flow of groundwater that has reached the surface is a(n)
a. spring.
c. aquifer.
b. well.
d. travertine.

The graph indicates the running route for tobias. which best describes his run? from time 0 to 6, he went fast and then slowed down. from time 6 to 10, he was at his slowest. from time 12 to 14, he went very slow. from time 14 to 18, he went toward the starting point.