Write down the balanced equation for the reaction when:
Carbon dioxide is passed through a concentrated aqueous solution of sodium chloride saturated with ammonia.

The value of the expression $$\sqrt 3 \,\cos \,ec\,{20^0} - \sec \,{20^0}$$ is equal to

For any two complex numbers $${z_1},{z_2}$$ and any real number a and b.

$$\,{\left| {a{z_1} - b{z_2}} \right|^2} + {\left| {b{z_1} + a{z_2}} \right|^2} = .........$$

The cube roots of unity when represented on Argand diagram form the vertices of an equilateral triangle.