A radioactive nucleus undergoes a series of decay according to the scheme

If the mass number and atomic number of `A` are `180` and `72`, respectively, what are these number `A_(4)` ?.

Explanation

To solve the problem, we need to analyze the decay processes of the radioactive nucleus A, which has a mass number (A) of 180 and an atomic number (Z) of 72. The decay process involves alpha decay, beta decay, and gamma decay. Let's break down the steps:

### Step-by-Step Solution:

1. **Identify the initial values of A:**
- Mass number (A) = 180
- Atomic number (Z) = 72

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