Task: Question Answering
Input (English): Passage: A half-hour remains before the show is to begin. Electrician Sidney and chorus girl Jeanie are irritated at Sidney's fellow electrician, Bob, for not being there. Sidney needs Bob's help; Jeanie, Bob's girlfriend, is annoyed at being stood up. Sidney warns Jeanie that Bob may not be the right man for her; these are doubts she has too (Musical numbers: "A Very Special Day"/"That's the Way it Happens").
Jeanie leaves, and Bob appears. Bob tells Sidney he likes dating Jeanie, but does not plan to marry her. When Sidney jokes that Jeanie can do better than Bob, the larger man momentarily chokes him. Jeanie sees this, adding to her doubts about Bob. Larry, the assistant stage manager, is also attracted to Jeanie (reprise of "That's the Way it Happens").
Stage manager Mac sees to the final preparations, and the overture to the internal show is played by the orchestra, led by Dario, the conductor ("Overture to Me and Juliet"). The internal show's curtain rises ("Marriage Type Love"): the main male character, "Me" (performed by Charlie, a singer), tells the audience about the girl he wants to marry, Juliet (Lily, a singer). He also tells the audience of the girl he is determined not to marry, Carmen, who scares him. "Me" feels Carmen (the lead female dancing role) is better suited to his boss, Don Juan (the lead male dancer). As the internal show continues, Bob and Sidney are on the light bridge. Bob identifies with Don Juan for his reluctance to marry ("Keep It Gay").
Another day at Me and Juliet, and the dancers are practicing under Mac's supervision (conclusion of "Keep It Gay"). At Larry's urging, Jeanie decides to audition for the position of second understudy for the role of Juliet. On learning this, Mac takes Larry aside and warns him never to get involved with a cast member of a show while in charge of it. No sooner has Mac said this than his girlfriend Betty (currently in the show across the street) auditions for the role of Carmen. The producer gives her the role. As Larry looks on with amusement, Mac accepts this professionally, then stamps off in disgust.
Jeanie practices for her own audition ("No Other Love"), and Larry tells her that the audience will accept her if she's "a real kid" like Juliet, but reject her if she's a "phony" ("The Big Black Giant"). Larry desires a romance with Jeannie, but fears the larger and stronger Bob.
Several months pass, during which Jeanie gets the job as second understudy. Larry and Jeanie are meeting secretly and keeping their budding romance from Bob. The rest of the cast is aware of their dates—one dancer spotted them in a chili restaurant on Eighth Avenue.
Mac, true to his principles, has dumped Betty, but the two are still attracted to each other. Betty enjoys acting ("It's Me"). As she performs in the internal show, Bob and Sidney are on the light bridge again. 
Question: What is the name of the person performing the internal show while Bob and Sidney are on the light bridge again?
Output (English): Betty.