It is given convex quadrilateral and a circle

with radii

inscribed in

.
Incircles radii of the triangles

,

,

,

are

,

,

,

.
a) Is it possible to find a dependency between

,

,

,

?
b) Is it possible express

in therms of

,

,

,

?
c) If a) and/or b) is true what is the dependency?