hi Ayat,
I repeat my self again
Times of Call Attempt- calls made by subscriber during that period
Times of Seizure- is calls attempt and given resoources( usually same as attempted calls if no congestion)
Times of Through Connection- calls which ring.
Times of Reply- calls which ring and answered
BHCA=(60*Calls attempted)/duration(Minutes)
in our case BHCA=60*3/5 =36