For the following two (02) items:
Let p = cosec 20° and q = cosec 70°.

What is $\frac{p^{2}+q^{2}}{p^{2}q^{2}}$ equal to?

For the following two (02) items:
Let $\cos (2x+3y)=\frac{1}{2}$ and $\cos (3x+2y)=\frac{\sqrt{3}}{2}$  where  $-\pi <(2x+3y)<\pi $ and $-\pi <(3x+2y)<\pi .$

How many values does (x + y) have?

For the following two (02) items:
Let $\cos (2x+3y)=\frac{1}{2}$ and $\cos (3x+2y)=\frac{\sqrt{3}}{2}$  where  $-\pi <(2x+3y)<\pi $ and $-\pi <(3x+2y)<\pi .$

How many values does (y-x) have?

For the following two (02) items:
Consider the equation abx² + bcx + ca = cax² + abx + bc

If the roots of the equation are equal, then which one of the following is correct?