\( 1 \leftarrow \quad \) Factor completely. If a polynomial is prime, state this.

\( \int e ^ { - \frac { x ^ { 2 } } { 2 } } x ^ { 3 } d x \)

Given events \( C \) and \( D \) with probabilities \( P(C)=0.3, P(D)=0.2 \), and \( P(C \) and \( D)=0.1 \), are \( C \) and \( D \) independent?

4. \( \left(\frac{1}{5}\right)^{4}\left(\frac{25}{14}\right)^{2}= \)

Z scores are reported as the same measurement unit as the raw scores.

5. En la proporcion \( \frac{x}{5}=\frac{6}{15} \) el valor de \( x \) es