<Li> Dennis Bowen as Todd Ludlow, a nerdy academic high achiever . </Li> <Li> Geoffrey Stump as Kyle "the Heartbreaker" Lucas </Li> <Li> Irene Arranga as Mary Johnson, later became Arnold Horshack's wife . </Li> <Li> Melonie Haller as Angie Grabowski, introduced in Season 3 as the only official female Sweathog but was gone by the end of the season . </Li>

Who played mary johnson on welcome back kotter