Q1: does "i've got your back"="I have you to support me?" “You just want to play in the secret passage.” “Well, who wouldn’t? He hurt you, Eli. He hurt my friend. He would have hurt me. I’m not going to sit at Maureen’s. Together, or not at all.” “That sounds like an ultimatum.” “Because it is.” She lifted her shoulders, let them fall in the most casual gesture. “We can fight about it. You can get mad, I can be in-sulted. I just don’t see the point, especially on such a gorgeous morning when we’re in love. The point I see, Eli, is I’ve got your back. And I know you’ve got mine.” What the hell was he supposed to do with that? “It might not work.”“Negative thinking’s unproductive. Plus, past history and pattern say it will work. This could be over, Eli, or at the very least he could be in police custody, charged with breaking and entering, maybe destruc-tion of property, by tonight. And he’d be questioned on all the rest.” She leaned forward. “When that happens, Wolfe’s going to have his first taste of crow.” “You had that ace up your sleeve,” Eli replied. “It’s karma time, Eli.”Q2: what does "past history and pattern say it will work"mean? what does "pattern"here mean?Q3: what does "have his forst taste of crow"mean?Q4:does "ace up your sleeve"= the way she has to accomplish sth?