Explanation

$\frac{\lbrack Energy\rbrack}{\lbrack Volume\rbrack} = \frac{\lbrack ML^{2}T^{- 2}\rbrack}{\lbrack L^{3}\rbrack} = \lbrack ML^{- 1}T^{- 2}\rbrack$ [pressure]=$\frac{\lbrack MLT^{- 2}\rbrack}{\lbrack L^{2}\rbrack} = \lbrack ML^{- 1}T^{- 2}\rbrack$