If the straight lines $2x + 3y - 3 = 0$ and $x + ky + 7 = 0$ are perpendicular,then the value of $k$ is:

$A$ line $L$ passing through the point $(2,0)$ makes an angle $60^{\circ}$ with the line $2x-y+3=0$. If $L$ makes an acute angle with the positive $X$-axis in the anticlockwise direction,then the $Y$-intercept of the line $L$ is:

The equations of the lines passing through the point $(3,2)$ and making an acute angle of $45^{\circ}$ with the line $x-2y-3=0$ are

The acute angle between the lines $x \sin \theta - y \cos \theta = 5$ and $x \sin \alpha - y \cos \alpha + 11 = 0$ is

To which of the following types do the straight lines represented by $2x + 3y - 7 = 0$ and $2x + 3y - 5 = 0$ belong?

If $S_1$ and $S_2$ are two straight lines such that the reflection of $S_1$ in $S_2$ and the reflection of $S_2$ in $S_1$ coincide,the angle between $S_1$ and $S_2$ is equal to?