The volume \( V \) of a rectangular prism can be calculated using the formula:
\[ V = \text{length} \times \text{width} \times \text{height} \]
For the given dimensions of the prism:
- Length = 7 cm
- Width = 3 cm
- Height = 2 cm
Substituting these values into the formula:
\[ V = 7 , \text{cm} \times 3 , \text{cm} \times 2 , \text{cm} \]
Calculating this step by step:
\[ V = 7 \times 3 = 21 , \text{cm}^2 \]
Now, multiply by the height:
\[ V = 21 , \text{cm}^2 \times 2 , \text{cm} = 42 , \text{cm}^3 \]
Therefore, the volume of the rectangular prism is
\[ \boxed{42 , \text{cm}^3} \]