Which of the following radiations `alpha,beta and gamma` are :
travel with greatest speed ?

Explanation

To determine which of the following radiations—alpha, beta, and gamma—travels with the greatest speed, we can analyze each type of radiation based on their properties.

### Step-by-Step Solution:

1. **Identify the Types of Radiation**:
- Alpha radiation consists of alpha particles, which are helium nuclei (2 protons and 2 neutrons). They are relatively heavy and carry a positive charge.
- Beta radiation consists of beta particles, which can be either electrons (beta minus) or positrons (beta plus). They are much lighter than alpha particles and carry a negative or positive charge, respectively.
- Gamma radiation consists of gamma rays, which are high-energy electromagnetic waves. They have no mass and no charge.
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