64seconds3 n N! c1 N1 D
( U9 N' P! k- m6 O; E, d V1 to 4 have 3floors = 48 sec! b: q" V0 _: H5 w- c9 s
avg. 48/3 = 16sec
+ H( l R3 \# Y+ c& ^3 E
$ c$ m' X H! J$ h2 {tvb now,tvbnow,bttvb4 to 8 have 4floors = 16x4
' ~3 ^' p$ f8 @( k. W b d/ {, y& g= 64secs |