Which of the following are models for perpendicular lines :
The lines of a railway track.

Answer

To determine whether the lines of a railway track are models for perpendicular lines, we can follow these steps:

### Step 1: Understand the definition of perpendicular lines
Perpendicular lines are two lines that intersect at a right angle (90 degrees). This means that when they cross each other, they form four right angles.

**Hint:** Remember that perpendicular lines meet at a specific angle, which is 90 degrees.

### Step 2: Analyze the lines of a railway track
Railway tracks consist of two parallel lines that run alongside each other. These lines are designed to ensure that trains can travel smoothly without any obstruction.

**Hint:** Think about how railway tracks are structured. Do they cross each other at any point?

### Step 3: Determine if the railway tracks intersect
Since railway tracks are parallel, they do not intersect at any point. This means they will never meet, regardless of how far they extend.

**Hint:** If two lines never meet, can they be considered perpendicular?

### Step 4: Conclusion
Since the lines of a railway track do not intersect and are parallel, they cannot be models for perpendicular lines. Therefore, the lines of a railway track are not perpendicular.

**Final Answer:** The lines of a railway track are not models for perpendicular lines; they are parallel lines.

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