You are relaxing in your stationary yacht. You see a fishing boat due north. Your laser range finder tells you that it is 2 nautical miles away. The boat is moving in a straight line in a very roughly southeasterly direction. You do know that it is moving at 4 knots (because, let's presume, that's what fishing boats do when reeling in their gear). After one hour your laser range meter measures your distance to the boat as 3 nautical miles. Unfortunately your compass is no longer working. Undaunted, you compute your bearing to the boat as degrees.
Hint: Moving at one knot means moving at one nautical mile per hour. Draw a picture. Consider two right triangles. Apply the Pythagorean Theorem and an inverse trig function.