Given The graph represents the number of students slept for a number of hours
We need to find the number of students slept 540 or more minutes
1 hour = 60 minutes
so, 540 minutes = 9 hours
so,we need to find the number of students slept 9 or more hours
From the diagram :
The number of students slept 9 hours = 8
The number of students slept 10 hours = 15
The number of students slept 11 hours = 3
So, the number of students = 8 + 15 + 3 = 26 students
So, the answer is option D. 26 students