To find the distance from the top of the flag pole to the tip of its shadow, we can use the Pythagorean Theorem.
Let's denote:
- the height of the flag pole as one leg of the right triangle, which is 20 feet,
- the length of the shadow as the other leg of the right triangle, which is 15 feet,
- the distance from the top of the flag pole to the tip of its shadow as the hypotenuse.
According to the Pythagorean Theorem:
\[ a^2 + b^2 = c^2 \]
where \(a\) and \(b\) are the legs of the triangle, and \(c\) is the hypotenuse.
Plugging in the values we have:
\[ 20^2 + 15^2 = c^2 \]
Calculating the squares:
\[ 400 + 225 = c^2 \]
This results in:
\[ 625 = c^2 \]
Taking the square root of both sides to find \(c\):
\[ c = \sqrt{625} = 25 \text{ feet} \]
So, the distance from the top of the flag pole to the tip of its shadow is 25 feet.
Therefore, the correct response is:
25 feet.