Final answer:
The greatest increase in running distance over the previous week occurs in Week 2 and Week 5, with each week showing a 0.5 mile increase.
Step-by-step explanation:
To determine which week shows the greatest increase in distance over the previous week in the student's running plan, we compare the differences in running distances from week to week:
- From Week 1 to Week 2: 1 mile to 1 1/2 miles = 0.5 mile increase
- From Week 2 to Week 3: 1 1/2 miles to 1 3/4 miles = 0.25 mile increase
- From Week 3 to Week 4: 1 3/4 miles to 2 miles = 0.25 mile increase
- From Week 4 to Week 5: 2 miles to 2 1/2 miles = 0.5 mile increase
- From Week 5 to Week 6: 2 1/2 miles to 2 3/4 miles = 0.25 mile increase
- From Week 6 to Week 7: 2 3/4 miles to 3 miles = 0.25 mile increase
Comparing these increases, the weeks with the greatest increase are Week 2 and Week 5, each with a 0.5 mile increase over the previous week. So, the correct answer is (d) Week 2 and 5.