<span>The problem says that the distance D to the horizon is directly proportional to the square root of the elevation E of the observer, so: </span> The person who is 36 feet above the water ⇒ √36=6
A person 49 feet above the water ⇒ √49=7 <span> So, by proportions, you have:
(7/6)x7.4= 8.63 miles
Therefore, the answer is: </span><span>a person 49 feet above the water can see 8.63 miles</span><span></span>