`""_(90)^(234)Th` disintegrates to give `""_(82)^(206)Pb` as the final product. How many `alpha- and beta`-particles are emitted during the process?

Explanation

To determine how many alpha and beta particles are emitted during the disintegration of thorium-234 (Th) to lead-206 (Pb), we can follow these steps:

### Step 1: Identify the initial and final atomic numbers and mass numbers
- **Initial (Thorium)**:
- Atomic number (Z) = 90
- Mass number (A) = 234
- **Final (Lead)**:
- Atomic number (Z) = 82
...