2
#$$%
●
Reversibility&'(#)'
*#*+$'**(*
*
●
Concurrenc y&'#$'*)'$
$)+($$$,$*+$$
**$*#*
●
History&'*'*
-$'$$$$$*$
.#$)($$$
$*'/)0$1'
#'$))$$$*#
($*$$'($