M shell of two elements A and B have 18 electrons each. The difference in the number of electrons present in N shell of A and B is 8. M shell is the penultimate shell in B. Predict the range of probable atomic numbers of A and B.

Explanation

To solve the problem, we need to analyze the information given about elements A and B, specifically focusing on their electron configurations.

### Step 1: Understand the Electron Configuration
- The M shell can hold a maximum of 18 electrons. Since both elements A and B have 18 electrons in their M shell, we can denote this as:
- A: M shell = 18 electrons
- B: M shell = 18 electrons

### Step 2: Determine the N Shell Electrons
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