Answer with explanation:

There are 100 students in the group.
If we divide 100 students into groups
→First quartile =25.5
means, first quartile of students has median value ≤ 78.
→Median =50.5
Most of the students sends ,90 messages a day.
→Third Quartile=75.5
Students lying above the third Quartile ,sends ≥102 messages per day.
First Quartile means, approximately 0- 25 students in the group , sends 78 messages.

Third Quartile means, 75-100 , students in the group, sends 102 messages .

Approximately 25 students in the sample send
1. more than 102 text messages.
2.less than 78 text messages.