<p>Carly Fiorina and Donald Trump are going at it — again. </p><p> On Friday afternoon, the billionaire businessman had some harsh words for his fellow Republican presidential candidate via Twitter. And Trump asked Fiorina to do something he rarely does himself: apologize.</p> <p>Trump’s tweets came after Fiorina posted on Facebook late Thursday night, calling out Trump for comparing Ben Carson’s comments about his violent past to those about a child molester, first on CNN, and later at a campaign rally in Iowa on Thursday night.</p> <p>Fiorina also referenced a moment during the debate when Trump called our Fiorina for interrupting.