Myiah rides her bike from home to the park to meet a friend. When she arrives at the park, Myiah and her friend sit at a park bench and talk. Myiah then rides her bike home at a slower rate. Which graph represents this situation?

Myiah rides her bike from home to the park so there is a distance from home, then she and her friends stay some time at the park, then the distance vs time is a horizontal line because they don't move while the time is moving. Finally, she rides her bike home at a slower rate, so she takes more time to get home.
In conclusion, the graph that represents this situation is the third.