436. Your vessel is steering 049° T at 15 knots. At 1914 a light bears 078° T, and at 1951 the same light bears 116° T. What will be your distance off abeam?

The distance off abeam is calculated using the formula b = D * (sin α * sin β) / sin (β - α), where D is the distance run, α is the first bearing, and β is the second bearing. Applying this formula with the given values yields a distance of 6.7 nautical miles.