Questions in trigonometry

Select	Question
	If the radius of the circumcircle of an isosceles triangle $PQR$ is equal to $PQ(=PR),$then the angle P is
	In a triangle ABC, $a:b:c=4:5:6$. The ratio of the radius of the circumcircle to that of the incircle is
	Which is true in the following
	If $x,\,y,\,z$are perpendicular drawn $a,\,b$ and $c$, then the value of $\frac{bx}{c}+\frac{cy}{a}+\frac{az}{b}$will be
	If the length of the sides of a triangle are 3, 4 and 5 units, then R (the circumradius) is
	If R is the radius of the circumcircle of the $\Delta ABC$and $\Delta $is its area, then
	The sum of the radii of inscribed and circumscribed circles for an n sided regular polygon of side a, is
	In a $\Delta ABC,\ {{r}_{1}} < {{r}_{2}} < {{r}_{3}},$then
	The radius of the incircle of triangle when sides are 18, 24 and 30 cms is
	If the sides of the triangle are $5K,\ 6K,\ 5K$and radius of incircle is 6 then value of K is equal to