Answer:
For the first one, it will be " Mary is at work" because it is 10 miles away from home.
For the second one, it will be " Mary is walking back to work" because it has not changed in miles but only in time.
For the third one, it will be " Mary is walking towards home but she notices she forgot her wallet" because it has a bit of a spike for the miles.
For the last one, it will be " Mary is walking towards home and eventually gets there" because it goes to 0 miles
Explanation: