............................................................................................................ 4 .........................................................................................................4 ....................................................6 .............................................................................................................................. 8 ..................................................................... 9 ...................................................... 9 12 ................................................................................................................................................... 16 ............................................................................................................................ 17 ............................................................................................................................... 18 ......................... 18 ..20 ..................................21 .........................................................................................................22 ............................................................................................................................ 23 ................................................................................................................ 24 ........................................................................................................24 ............................................................................................................................ 25