For a transistor `beta = 40 and I_B = 25 mu A.` Find the value of `l_E `.

Explanation

To solve the problem, we will follow these steps:

### Step 1: Understand the relationship between the currents in a transistor
For a transistor, the relationship between the emitter current (I_E), collector current (I_C), and base current (I_B) is given by the equation:
\[ I_E = I_C + I_B \]

### Step 2: Use the given beta value to find I_C
We know that the current gain (beta) of a transistor is defined as:
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