S$_\text{N}2$ reactions are stereospecific and proceed via a backside attack, resulting in the inversion of configuration at the chiral center.
S$_\text{N}1$ reactions occur via a carbocation intermediate, which is planar. As a result, nucleophiles can attack from either side, leading to a racemic mixture of products.
Thus:
\[ \text{S$_\text{N}2$} \rightarrow \text{Inversion (stereospecific)}, \quad \text{S$_\text{N}1$} \rightarrow \text{Racemization}. \]
Both statements are correct.
Let one focus of the hyperbola $ \frac{x^2}{a^2} - \frac{y^2}{b^2} = 1 $ be at $ (\sqrt{10}, 0) $, and the corresponding directrix be $ x = \frac{\sqrt{10}}{2} $. If $ e $ and $ l $ are the eccentricity and the latus rectum respectively, then $ 9(e^2 + l) $ is equal to: