Final answer:
The distance to the river is approximately 5.67 km. The distance to the river is approximately 5.67 km. Option d) Not determinable from the given information is the correct answer.
Step-by-step explanation:
The information given in the student's question is not sufficient to accurately determine the distance from the oil refinery to the river. The question mentions that the refinery is located on the north bank 1 km from the center of the river and at 80 degrees from due north. However, this information does not provide any lengths or angles that could help us construct a right triangle or use trigonometry to find the distance to the river bank. Hence, the correct answer should be (d) Not determinable from the given information.
To find the distance to the river, we can use trigonometry. Since the refinery is at 80 degrees from due north and is located 1 km from the center of the river, we can form a right triangle. The opposite side of the triangle represents the distance to the river, and the adjacent side represents the 1 km distance. We can use the tangent function to find the distance to the river.
Tan(80 degrees) = Opposite / Adjacent
Opposite = Tan(80 degrees) * 1 km ≈ 5.67 km
Therefore, the distance to the river is approximately 5.67 km. Option d) Not determinable from the given information is the correct answer.