MEXICO CITY/SAN FRANCISCO (Reuters) – SurveyMonkey Chief Executive Dave Goldberg died Friday from a head injury while exercising at a resort in Mexico, the local prosecutor’s office said Monday. Goldberg, the husband of Facebook Inc (FB.O) Chief Operating Officer Sheryl Sandberg, fell off a treadmill at a private villa in Punta Mita and hit his head, the prosecutor’s spokesman said. Goldberg’s brother found him on the floor of the villa gym showing signs of life, the spokesman said. Goldberg was taken to the hospital, where he later died.