Final answer:
The distance from the port is calculated by considering the two legs of the ship's journey. The first leg is a straight path due north, while the second leg is on a bearing of N 20º E. By using the Pythagorean theorem or trigonometry, we can determine the hypotenuse of the right triangle formed by these paths to find the total distance from the port.
Step-by-step explanation:
The question asks us to calculate the distance of a ship from the port at a specific time, which involves understanding and applying the concepts of bearings and distance travelled in a two-dimensional plane. To find the distance the ship is from the port at 4 pm, we need to consider the two legs of the journey. For the first leg, from 1 pm to 3 pm, the ship travels due north at 30 miles/hour for 2 hours, totalling 60 miles. During the second leg, from 3 pm to 4 pm, it travels on a bearing of N 20º E for 1 hour at the same speed. The distance covered during the second leg would be 30 miles. To find the total distance from the port, we need to construct a right triangle with the two legs of the journey and use the Pythagorean theorem or trigonometry to calculate the hypotenuse, which represents the distance from the port.