What thermodynamics variable is defined by (a) Zeroth law (b) First law?

Explanation

To answer the question regarding the thermodynamic variables defined by the Zeroth and First Laws of Thermodynamics, we can break it down step by step.

### Step-by-Step Solution:

1. **Understanding the Zeroth Law of Thermodynamics**:
- The Zeroth Law establishes the concept of temperature. It states that if two systems are each in thermal equilibrium with a third system, then they are in thermal equilibrium with each other.
- **Thermodynamic Variable Defined**: **Temperature**. This law allows us to define temperature scales and understand thermal equilibrium.

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