State whether the following statements are true or false: Appearance of Halley's Comet once in every 76 years is a periodic change.

Explanation

To determine whether the statement "Appearance of Halley's Comet once in every 76 years is a periodic change" is true or false, we can follow these steps:

### Step 1: Understand the Concept of Periodic Change
- A periodic change is defined as a change that occurs at regular intervals of time. This means that the event happens repeatedly after a specific duration.

**Hint:** Think about events that happen regularly, like seasons or the phases of the moon.

### Step 2: Analyze Halley's Comet
- Halley's Comet is known to appear approximately every 76 years. This means that it follows a predictable schedule and can be observed from Earth at regular intervals.

**Hint:** Consider how often you see certain events in nature, like a flower blooming every spring.

### Step 3: Determine the Nature of Halley's Comet's Appearance
- Since Halley's Comet takes 76 years to complete one orbit around the Sun and reappears after this time, it fits the definition of a periodic change.

**Hint:** Reflect on how a clock ticks at regular intervals, marking the passage of time.

### Step 4: Conclusion
- Based on the understanding that Halley's Comet appears every 76 years, we can conclude that the statement is true.

**Final Answer:** The statement is **True**.

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