Show that \( f(x) = |x| \, \textbf{is continuous at} \, x = 0.\)
If \[ P(A) = \frac{3}{13}, P(B) = \frac{5}{13}, \text{and} P(A \cap B) = \frac{2}{13}, \] \(\text{then find the value of }\) \( P(B|A) \).
If \[ P(A) = 0.4 \, \text{and} \, P(B) = 0.5, \, \text{also, A and B are independent events, then find} \] (i) \( P(A \cup B) \) and (ii) \( P(A \cap B) \).
Find the minimum value of \[ Z = 50x + 70y \] \(\text{under the following constraints by graphical method:}\) \[ 2x + y \geq 8, \] \[ x + 2y \geq 10, x \geq 0, y \geq 0. \]
If \[ A = \begin{bmatrix} 1 & 3 & 3 \\ 1 & 4 & 3 \\ 1 & 3 & 4 \end{bmatrix}, \] \(\text{then prove that}\) \[ A \cdot \text{adj}(A) = |A| \cdot I. \text{ Also, find } A^{-1}. \]