If a group of trunk is offered 1200 calls during the busy hour & 20 calls are lost along with the average call duration of about 7 min, then what would be the total duration of congestion period?

If a group of trunk is offered 1200 calls during the busy hour & 20 c

1.	If a group of trunk is offered 1200 calls during the busy hour & 20 calls are lost along with the average call duration of about 7 min, then what would be the total duration of congestion period?
A.	21.6 sec
B.	42.2 sec
C.	57.6 sec
D.	98.2 sec
Answer» D. 98.2 sec