Answer:
27.8°
Step-by-step explanation:
The mnemonic SOH CAH TOA reminds you that the relationship between the angle and the relevant sides of the triangle is ...
Cos = Adjacent/Hypotenuse
In this case, the hypotenuse of the triangle is the length along the road; the distance parallel to the ground is the side adjacent to the angle of depression. So, you have ...
cos(angle) = (23 mi)/(26 mi)
angle = arccos(23/26) ≈ 27.8°
The angle of depression is about 27.8°.
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Comment on the road
The grade on such a road is about 53%. A road with an 8% grade for any distance is considered marginally safe for trucks. A 53% grade for 26 miles would wear out the brakes in no time.
The elevation drop on this road is about 12 miles, or more than 64,000 feet. The highest mountain on Earth is less than half that height, so this must be on a different planet.
