64seconds
' y6 i" D/ m$ w5 R5.39.217.776 Z/ Z$ n# j1 [1 X6 L( n
1 to 4 have 3floors = 48 sectvb now,tvbnow,bttvb! D* }/ f3 j! B4 O5 i+ A4 U
avg. 48/3 = 16sectvb now,tvbnow,bttvb3 s9 Y$ L5 h2 p+ U/ R" X
2 E7 p- H) p; q3 {( Y4 to 8 have 4floors = 16x4
. ]0 J0 s! Q, r* \5 Y) l0 l% L5.39.217.77= 64secs |