64secondstvb now,tvbnow,bttvb/ N9 u5 V# ?5 C2 R& K2 d
. h' I* \8 H. V' q. s" q1 to 4 have 3floors = 48 sec ]# J- z" c" `4 R9 x3 c
avg. 48/3 = 16sec
W0 S4 k9 j( r; Z, b Ntvb now,tvbnow,bttvb& ^$ j, {) A, z7 S
4 to 8 have 4floors = 16x4
4 D5 x# Z: Y$ W5 R; N= 64secs |