Final answer:
A pentagon has five corners; therefore, the commissioner will place five fountains at the corners of the pentagon-shaped park.
Step-by-step explanation:
The question states that a park commissioner designs a new playground in the shape of a pentagon and plans to have a fountain at every corner of the park. A pentagon by definition has five sides, and accordingly, it will also have five corners. Therefore, for the playground shaped as a pentagon, there will be five fountains, one at each corner.
To answer the multiple-choice question: How many fountains will there be at every corner of the pentagon-shaped park? The correct answer is (B) 5. This is because a pentagon always has five corners regardless of its size or dimensions.