2 “ who shot her?” cried Rogers as he rushed into the hospital after his ex-wife died from a bullet through her head. "Mr. Rogers," said Professor Stiggins. "We'll have to ask you a few questions,. Although divorced for the past six months, you have been living in the same house with your ex-wife, have you not?“ "That's right," replied Rogers. "Had any trouble recently?" "Well, yesterday, when I told her I was going on a business trip, she threatened to commit suicide. I Returned to town this afternoon," continued Rogers, "I called my home and the maid answered.“ “Just what did she say?” inquired Stiggins. 'Oh, Mr. Rogers, they took poor mistress to St. Ann's Hospital about half an hour ago. Please hurry to her.’ "She was crying, so I couldn't get anything else out of her; then I hurried here. Where is she?" the professor told the inspector, "you'd better detain Mr. Rogers. If he didn't shoot her himself, I'm confident he knows who did." Why did the professor advise the Inspector to detain Rogers?