I believe your answer is -0.25n+0.75
AB is a diameter of the circle, so it divides circle into two semicircles.
Inscribed Angle Theorem:
The measure of an inscribed angle is half the measure of the intercepted arc.
An especially interesting result of the Inscribed Angle Theorem is that an angle inscribed in a semi-circle is a right angle. That's why m∠<span>AQB=m∠</span><span>ASB=m∠</span><span>ALB=m∠</span><span>ATB=m∠</span><span>ARB=90°.</span>
It is impossible to find measure of ∠<span>BWD, its measure depends on measure of a central angle ∠WDB. </span>
Formula is (x-h)2+(y-k)2=r2