The surface area of a triangular prism can be represented by the formula:
\[ \text{S.A.} = \text{Base Area} + (S_1 + S_2 + S_3) \times \text{Height} \]
Where:
- "Base Area" is the area of the triangular base.
- \( S_1, S_2, S_3 \) are the lengths of the sides of the triangular base.
- "Height" is the length of the prism (the distance between the two triangular bases).
So, filling in the question marks, we have:
The surface area of a triangular prism is
\[ \text{S.A.} = \text{Base Area} + (S_1 + S_2 + S_3) \times \text{Height} \]