Questions in st-line

Select	Question
	The angle between the lines $y=(2-\sqrt{3})x+5$ and $y=(2+\sqrt{3})x-7$ is
	The angle between the lines whose intercepts on the axes are a, – b and b, – a respectively, is
	If the coordinates of the vertices A, B, C of the triangle ABC be $(-\ 4,\ 2),$ $(12,\ -2)$ and $(8,\ 6)$ respectively, then $\angle \ B =$
	Angle between the lines $\frac{x}{a}+\frac{y}{b}=1$ and $\frac{x}{a}-\frac{y}{b}=1$ is
	If the lines $y=3x+1$ and $2y=x+3$ are equally inclined to the line $y=mx+4,$ then $m =$
	The angle between the lines $x\cos {{\alpha }_{1}}+y\sin {{\alpha }_{1}}={{p}_{1}}$ and $x\cos {{\alpha }_{2}}+y\sin {{\alpha }_{2}}={{p}_{2}}$ is
	The angle between the lines $x\cos {{30}^{o}}+y\sin 30{}^\circ =3$ and $x\cos {{60}^{o}}+y\sin {{60}^{o}}=5$ is
	The angle between the two lines $y-2x=9$ and $x+2y=-\ 7,$ is
	If $\frac{1}{a{b}'}+\frac{1}{b{a}'}=0,$ then lines $\frac{x}{a}+\frac{y}{b}=1$ and $\frac{x}{{{b}'}}+\frac{y}{{{a}'}}=1$ are
	To which of the following types the straight lines represented by $2x+3y-7=0$ and $2x+3y-5=0$ belong