H
NE
T THE
25
23
30
35
O
a)
25, 18, 22, 24, 28, 30, 35, 40,25, 18, 25,22,25,24,28,30,25,22,
18,28,24,35,30,25,40,25,18,22,18,30
years for 30 teachers of a school.​