The atomic number of three elements A, B and C are given below :
`{:("Element",A,B,C),("Atomic number",5,7,10):}`
Answer the following:
(a) Write the group number of the three elements in the Modern Periodic Table.
(b) Mention the period of these elements in the Modern Periodic Table.
(c) Out of these three elements which one has the smallest atomic radius and why ?

Explanation

To solve the question step by step, we will analyze the atomic numbers of elements A, B, and C, and determine their group numbers, periods, and atomic radii.

### Step 1: Identify the Elements
- **Element A** has an atomic number of 5. This corresponds to **Boron (B)**.
- **Element B** has an atomic number of 7. This corresponds to **Nitrogen (N)**.
- **Element C** has an atomic number of 10. This corresponds to **Neon (Ne)**.

### Step 2: Determine the Group Numbers
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