If the line $y=2x+c$ is a tangent to the circle $x^2+y^2=5$,then a value of $c$ is

The length of the tangent from the point $(4, 5)$ to the circle $x^2 + y^2 + 2x - 6y - 6 = 0$ is

If the lines $3x + 4y - 14 = 0$ and $6x + 8y + 7 = 0$ are both tangents to a circle,then its radius is

The equations of the tangents to the circle $x^2+y^2=36$ which are perpendicular to the line $5x+y-2=0$ are

If $PA$ and $PB$ are the tangents drawn from the point $P(1,1)$ to the circle $x^2+y^2+gx+gy-2=0$ with $C$ as the centre,then the area (in sq. units) of the quadrilateral $PACB$ is

$A$ tangent is drawn to the circle $2x^{2} + 2y^{2} - 3x + 4y = 0$ at point $A$ and it meets the line $x + y = 3$ at $B(2, 1)$. Then,the length of $AB$ is equal to: