Element A is hard, mallcable, ductile and react with dilute acids to produce salt and hydrogen is a good conductor of heat and electricity. Element B is soft, brittle and cannot be beaten to form thin sheets is a non-conductor of heat and does not react with dilute acids. Which of these elements is a metal?

Explanation

To determine which of the two elements, A or B, is a metal, we can analyze the properties of each element as described in the question.

### Step-by-Step Solution:

1. **Identify the Properties of Element A:**
- Element A is described as hard, malleable, ductile, and a good conductor of heat and electricity.
- It reacts with dilute acids to produce salt and hydrogen gas.

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