A77-year-old retired school superintendent comes to your office, complaining of unsteady hands. he says that for the past six months, when his hands are resting in his lap they shake uncontrollably. he says when he holds them out in front of his body the shaking diminishes, and when he uses his hands the shaking is also better. he also complains of some difficulty getting up out of his chair and walking around. he denies any recent illnesses or injuries. his past medical history is significant for high blood pressure and coronary artery disease, requiring a stent in the past. he has been married for more than 50 years and has five children and 12 grandchildren. he denies any tobacco, alcohol, or drug use. his mother died of a stroke in her 70s and his father died of a heart attack in his 60s. he has a younger sister who has arthritis problems. his children are all essentially healthy. on examination you see a fine, pill-rolling tremor of his left hand. his right shows less movement. his cranial nerve examination is normal. he has some difficulty rising from his chair, his gait is slow, and it takes him time to turn around to walk back toward you. he has almost no “arm swing” with his gait. what type of tremor is he most likely to have?