\[ \left( \frac{1}{{}^{15}C_0} + \frac{1}{{}^{15}C_1} \right) \left( \frac{1}{{}^{15}C_1} + \frac{1}{{}^{15}C_2} \right) \cdots \left( \frac{1}{{}^{15}C_{12}} + \frac{1}{{}^{15}C_{13}} \right) = \frac{\alpha^{13}}{{}^{14}C_0 \, {}^{14}C_1 \cdots {}^{14}C_{12}} \]
Then \[ 30\alpha = \underline{\hspace{1cm}} \]
\( z_1, z_2, z_3 \) represent the vertices A, B, C of a triangle ABC respectively in the Argand plane. If
\[ |z_1 - z_2| = \sqrt{25 - 12 \sqrt{3}}, \] \[ \left|\frac{z_1 - z_3}{z_2 - z_3}\right| = \frac{3}{4}, \] \[ \text{and } \angle ACB = 30^\circ, \]
Then the area (in sq. units) of that triangle is: