2. Given the tetrahedron $P-ABC$ with the base $\triangle ABC$ being an equilateral triangle with side length 3, $PA=3, PB=4, PC=5$. Then the volume of the tetrahedron $P-ABC$ is ( ).
(A) 3
(B) $\sqrt{10}$
(C) $\sqrt{11}$
(D) $2 \sqrt{3}$
2. C.
$$
\begin{array}{l}
V_{\text {tetrahedron } P-A B C}=V_{\text {tetrahedron } A-P B C} \\
=\frac{1}{3}\left(\frac{1}{2} \times 3 \times 4\right) \times \sqrt{3^{2}-\left(\frac{5}{2}\right)^{2}}=\sqrt{11} .
\end{array}
$$