Answer:
20 minutes
Step-by-step explanation:
For this question, it's important to think about how Mia stopping to change her tire might show on the graph, which marks marks distance and time.
Well, surely while she's changing the tire, the distance she's travelling will not be increasing as she will have stopped moving.
So we look to see if there's a point on the graph where the distance stops going up for a period, and there is! The distance travelled stops at 40m between 30 minutes and 50 minutes. So that means she is stopping to change her tire during this time.
If it took her form the 30 minute mark to the 50 minute mark to change the tire, the amount of time it took is 50minutes - 30minutes =20 minutes.