To find the volume of a rectangular prism, you can use the formula:
\[ \text{Volume} = \text{Base Area} \times \text{Height} \]
From the information given:
- The base area \( B = 21 , \text{cm}^2 \)
- The height \( h = 3 , \text{cm} \)
Now we can substitute these values into the formula:
\[ \text{Volume} = 21 , \text{cm}^2 \times 3 , \text{cm} = 63 , \text{cm}^3 \]
Therefore, the volume of the right rectangular prism is \( 63 , \text{cm}^3 \).
The correct response is: 63 cm³.