# spherical excess

## Area of a spherical triangle with given interior angles

**Problem**

Find the area of a spherical triangle of whose angles are 123°, 84°, and 73°. The radius of the sphere is 30 m.

A. 1863.3 square meter

B. 1570.8 square meter

C. 1958.6 square meter

D. 1480.2 square meter

## Spherical Trigonometry

**Spherical Triangle**

Any section made by a cutting plane that passes through a sphere is circle. A great circle is formed when the cutting plane passes through the center of the sphere. Spherical triangle is a triangle bounded by arc of great circles of a sphere.