(1) As soon as practicable after the commencement of an action brought as a class action, but never in a hearing without all representative plaintiffs and all defendants having been given an opportunity to be present, the court shall determine by order whether the action is to be so maintained. An order under this section may be conditional and may be altered or amended before the decision on the merits.(2) In any class action maintained under Rule 23.02(3), the court shall direct to the members of the class the best notice practicable under the circumstances, including publication when appropriate or individual notice to all members who can be identified through reasonable effort. The notice shall advise each member that (a) the court will exclude the member from the class if the member so requests by a specified date; (b) the judgment, whether favorable or not, will include all members who do not request exclusion; and (c) any member who does not request exclusion may, if the member desires, enter an appearance.(3) The judgment in an action maintained as a class action under Rule 23.02(1) or Rule 23.02(2), whether or not favorable to the class, shall include and describe those whom the court finds to be members of the class. The judgment in an action maintained as a class action under Rule 23.02(3), whether or not favorable to the class, shall include and specify or describe those to whom the notice provided in Rule 23.03(2) was directed, and who have not requested exclusion, and whom the court finds to be members of the class.(4) When appropriate (a) an action may be brought or maintained as a class action with respect to particular issues, or (b) a class may be divided into subclasses and each subclass treated as a class, and the provisions of this rule shall then be construed and applied accordingly.