I Can Do Bad All by Myself

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The film opens with April (Taraji P. Henson), a self-centered, alcoholic singer, performing at a nightclub where she works. On the other side of town, Madea (Tyler Perry) and Joe Simmons (Perry) catch Jennifer (Hope OlaidÃ¨ Wilson), Manny (Kwesi Boakye), and Byron (Freddy Siglar) breaking into their house. After hearing the childrenâs troubles, Madea welcomes and feeds them. Jennifer tells Madea that theyâre living with their grandmother, whom they haven't seen in four days. They tell Madea that their only other relative is their aunt April.
April shares her home with her shady boyfriend, Randy (Brian White), whoâs married with children. The next morning, Madea brings the kids to April's house, but April doesnât want to be bothered. Meanwhile, Pastor Brian (Marvin Winans) sends a Colombian immigrant named Sandino (Adam RodrÃ­guez) to her house for work and a place to stay. April puts Sandino in her basement and wants to lock him down there because she doesn't know him that well. While working around the house, Sandino surprises April by cleaning himself up and becoming very handsome. When Randy arrives, he sees April with the kids and Sandino and heckles him while making subtle advances at Jennifer.
Shortly afterward, Pastor Brian and Wilma (Gladys Knight), a church member, come to inform April that her mother died from a fatal brain aneurysm while riding on a bus. April is devastated by the news and seeks comfort from Randy; however, he is sleeping and shrugs her off. Later, Sandino comforts April as she tells him about her mother's death and the last time she spoke with her.
Depressed, Jennifer goes to Madea wanting to know how to pray. However, Madea, inexperienced with prayer, attempts to instruct her in a scene that plays out comically. The same night, Wilma sings "The Need to Be", an uplifting song for women, and Tanya (Mary J. Blige), the nightclub bartender, sings "I Can Do Bad". Before singing the song, Tanya is fed up with April's attitude and tries to help her friend, despite the fact that she can't help April if she canât help herself.
Over time, Sandino and April become friends, and Sandino fixes a ruined bedroom in her house. This makes Manny and Byron happy but not Jennifer, who feels April doesn't want them there. While on a date, Sandino tells April he doesn't understand why she is with Randy and asks if she loves Randy. He tells her what true love is to him. One Sunday morning, Sandino eagerly knocks on April's bedroom door to get April ready for church, but Randy threatens to kill Sandino if he continues to spend time with April.
Late one night, Manny needs his insulin shot, and Jennifer gets it for him in the kitchen. As Jennifer gets her brother's insulin, Randy approaches and attempts to rape her, but Sandino fights him off. April walks in on the fight and Randy claims Jennifer offered him sex for money. April claims to believe him and sends Randy to take a bath. When he is in the tub, April threatens to electrocute him with a plugged-in radio. Sandino arrives and tries to stop her, but April is enraged, as she explains that she was sexually assaulted by her step-father, who then lied about it to her mother, thus causing April to lose her faith in the people that cared about her. After saying Randy is no different from him, she drops the radio into the water, giving Randy a severe electric shock. Randy barely jumps out just in time and Sandino orders him to leave.
April goes to the bar for a drink and blames herself for not seeing the signs. Sandino tries to stop her from drinking, but she pushes him away. She then asks Sandino if he is a child molester, because of all the attention he gives the children. Sandino tells April of his childhood as a child laborer and explains that he loves the children so much because he sees himself in them. Feeling hurt at her unfair accusations, Sandino says farewell to the children and leaves.
Jennifer and April begin to get along and connect after April tells Jennifer about her bad experience as a child. Jennifer tells April that she should recognize Sandino as a good man. Eventually, Sandino returns and April apologizes to him and admits that she loves him like a friend. Sandino tells her that she can't love anyone until she learns to love herself. He tells April that he is in love with her but he wants April to love him back the same way he loves her. He shows her by kissing her.
Eventually, April and Sandino get married. April and Sandino then hold a block party for their reception with Tanya singing "Good Woman Down", dedicated to April, then the new couple is shown embracing and sharing a passionate kiss.

Question: What did April use to electrocute Randy in the bathtub?
Answer: Radio