 Shares of Jack in the Box Inc. JACK, -0.53 sank 8.2 in premarket trading Tuesday, after the burger chain reported fiscal fourth-quarter results that beat expectations but provided a downbeat full-year outlook, amid continued headwinds from the inflationary impact on margins. Net income for the quarter to Oct. 2 rose to 45.9 million, or 2.17 a share, from 38.9 million, or 1.80 a share, in the year-ago period. 