A runner runs or a racer races from the start line to the finish line on each of these tracks. Along which track can the distance covered by the runner/racer be measured?

Answer

To determine which track allows the distance to be accurately measured, we need to analyze each track based on its shape and structure. 1. **Track P** (circular track): This track is round and closed. The distance around a circular track can easily be measured using the formula for the circumference, which is \(C = 2\pi r\), where \(r\) is the radius. Thus, Track P effectively allows for distance measurement. 2. **Track Q** (jogging track): This track contains a garden and looks like an irregular shape but appears to be closed. If the borders of this track are defined, the distance can be measured similarly to Track P, although calculating the exact distance may be more complex depending on the shape. If it's clearly marked, it's measurable. 3. **Track R** (car racing track): This track also has a defined shape (a zig-zag pattern) and is closed. Like the previous tracks, as long as the track is continuous and the start and end lines are clearly marked, the distance covered can be measured. After analyzing all three tracks: - **Track P allows for straightforward distance measurement.** - **Track Q can be measurable, but it may depend on the boundaries being clear.** - **Track R also allows for distance measurement, as it's a closed and defined path.** However, considering the options presented (A to D) — - **Track P only could potentially measure distance, though not solely.** - **Track Q alone restricts accuracy based on irregularities.** - **Track R accurately measures distance as long as it's traversed in a specified manner.** Conclusion: All tracks allow for measurement cumulatively since they provide defined paths for running or racing, making option D (all tracks P, Q, and R) the most comprehensive choice for measuring distance.