 If you're a fiction writer, one of your most important goals is to get your reader lost in your story and to make sure that you don't trigger an alarm. And the alarm clock is the subconscious or the conscious mind of the reader saying, that doesn't sound right. This week on Planet Money, three novelists on how they inject economic facts into their fiction. And on How I Built This, the co-founder of Brimstone on a new way to make cement from NPR. Just ahead at noon on KNPR.