The maximum number of common tangents drawn to two circles when both the circles touch each other externally is 

In ΔABC, ∠C=90° and D is a point on CB such that AD is the bisector of ∠A. If AC=5 cm and BC=12 cm, then what is the length of AD?

In any triangle ABC, AB + BC = 12 cm, BC + CA = 14 cm and CA + AB = 18 cm. What will be length of radius of a circle, if the perimeter of circle is equal to the perimeter of triangle ABC? 

If in a triangle, the orthocenter lies on vertex, then the triangle is 

If there are four lines in a plane, then what cannot be the number of points of intersection of these lines? 

In a triangle ΔABC, the sides DE parallel to BC and AD = 6 cm, DB = 9 cm, AE = 8 cm, find the value of AC.

In the given figure, ∠QRU = 72°, ∠TRS = 15° and ∠PSR = 95°, then what is the value (in degrees) of ∠PQR ?

The sum of all interior angles of a regular polygon is twice the sum of all its exterior angles.  The number of sides of the polygon is