calculate the mass defect of Helium `[""._(2)He^(4)]`
mass of proton `=1.007276 u,`
Mass of neutron `=1.008665u,`
Mass of `""._(2) He^(4)= 1.001506 u,`

Explanation

To calculate the mass defect of Helium-4 \((^{4}_{2}\text{He})\), we will follow these steps:

### Step 1: Identify the number of protons and neutrons in Helium-4
Helium-4 has an atomic number of 2, which means it has:
- 2 protons
- The mass number is 4, so the number of neutrons = mass number - atomic number = 4 - 2 = 2 neutrons.

### Step 2: Calculate the total mass of the individual nucleons
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