Hence in trilinear co-ordinates, with **ABC** as fundamental triangle, its equation is Pa+Q/1+R7=o.

If four fluids, a, b, c, d, meet in a point 0, and if a tetrahedron AB CD is formed so that its edge AB represents the tension of the surface of contact of the liquids a and b, BC that of b and c, and so on; then if we place this tetrahedron so that the face **ABC** is normal to the tangent at 0 to the line of concourse of the fluids **abc**, and turn it so that the edge AB is normal to the tangent plane at 0 to the surface of contact of the fluids a and b, then the other three faces of the tetrahedron will be normal to the tangents at 0 to the other three lines of concourse of the liquids, an the other five edges of the tetrahedron will be normal to the tangent planes at 0 to the other five surfaces of contact.

Let us imagine unit mass of solution of volume V confined in a cylinder **ABC** between a fixed vapour sieve B and a solid piston A A B C FIG.

It is easily shown that the areas of the lune Adbea and the triangle **ABC** are equal.

On june harrah's be played at media company focused hbo espn **ABC**.