The expression $$ \sim $$ ($$ \sim $$ p $$ \to $$ q) is logically equivalent to :

$$\mathop {\lim }\limits_{x \to {1^ - }} {{\sqrt \pi - \sqrt {2{{\sin }^{ - 1}}x} } \over {\sqrt {1 - x} }}$$ is equal to :

The equation of a tangent to the parabola, x² = 8y, which makes an angle $$\theta $$ with the positive directions of x-axis, is :

If the sum of the first 15 terms of the series $${\left( {{3 \over 4}} \right)^3} + {\left( {1{1 \over 2}} \right)^3} + {\left( {2{1 \over 4}} \right)^3} + {3^3} + {\left( {3{3 \over 4}} \right)^3} + ....$$ is equal to 225 k, then k is equal to :