If the ratio of the measurement of the four angles of a quadrilateral is 1: 2: 3: 4, then the measurement of its smallest angle is-

ABCD is square and CDE is an equilateral triangle outside the square . What is the value ( in degrees ) of ∠BEC ? 

What is the length of the radius of the circumcircle of the equilateral triangle, the length of whose side is 6√3 cm?

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

Two equal circles of radius 4 cm intersect each other such that each passes through the center of the other. The length of the common chord is

The number of sides in two regular polygons are in the ratio of 5 : 4. The difference between their Interior angles of the polygon is 6⁰ . Then the number of sides are 

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