Before revision: T: 092 ° V: +3 ° M: 089° D: -4° C: 093° Thus, when following a compass course of 093°, the true course is 092°.
After revision: T: 086 ° V: -3 ° M: 089° D: -4° C: 093° Thus, when following a compass course of 093°, the true course is 092°.