If the elasticity of the demand `eta =1` then demand is

Options

A. constant
B. in elastic
C. unitary elastic
D. elastic

Answer

To determine the nature of demand when the elasticity of demand (η) is equal to 1, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Elasticity of Demand**:
- Elasticity of demand measures how much the quantity demanded of a good responds to a change in price or other factors. It is calculated as the percentage change in quantity demanded divided by the percentage change in price.

2. **Identifying the Value of Elasticity**:
- In this case, we are given that η = 1. This specific value indicates a particular type of demand.

3. **Interpreting η = 1**:
- When the elasticity of demand is equal to 1, it is referred to as "unitary elasticity." This means that the percentage change in quantity demanded is exactly equal to the percentage change in price.

4. **Conclusion**:
- Therefore, if the elasticity of demand is equal to 1, we conclude that demand is unitary elastic. This means that demand responds proportionately to changes in price.

### Final Answer:
If the elasticity of demand η = 1, then demand is **unitary elastic**.

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