Answer: 16 meters; -4 meters
Explanation:
For this question, you can ignore the times that were given to you.
a.) Let's start with distance. Distance is a total sum, regardless of direction. This student walked 6 meters, stands still (0 meters), 3 meters, and 7 meters. Sum up these values: 6+0+3+7 = 16 meters
b.) Displacement adds direction. The student walks 6 meters away. We will give this the +x-direction. They then walk 3 meters back towards the origin (-x-direction) and pause for a second. They continue to walk 7 more meters toward the origin (-x-direction). This time when we sum these values we must include the signs: 6+(-3)+(-7) = -4 meters. We can test this by referring to the sentence where it says they passed their starting point. This means they are now in the -x-direction and we have a negative displacement.
Hope this helps!