The modulus and amplitude of $\frac{1 + 2i}{1 - (1 - i)^2}$ are

Let $p = (x + 4y)\,a + (2x + y + 1)\,b$ and $q = (y - 2x + 2)\,a + (2x - 3y - 1)\,b,$ where $a$ and $b$ are non-collinear vectors. If $3p = 2q,$ then the values of $x$ and $y$ are:

Sodium is heated in air at $300^{\circ} C$ to form $X$. $X$ absorbs $CO_2$ and forms $Na_2CO_3$ and $Y$. Which of the following is $Y$?

In a transistor,if $\frac{I_C}{I_E} = \alpha$ and $\frac{I_C}{I_B} = \beta$. If $\alpha$ varies between $\frac{20}{21}$ and $\frac{100}{101}$,then the value of $\beta$ lies between:

If the axes are rotated through an angle $\alpha$,then the number of values of $\alpha$ such that the transformed equation of $x^2+y^2+2x+2y-5=0$ contains no linear terms is

The value of $\frac{3 + \cot 76^\circ \cot 16^\circ}{\cot 76^\circ + \cot 16^\circ}$ is: