What is the measure of angle A?

Answer:
84
Step-by-step explanation:
ang CDB is an inscribed angle of angle COB, thus COB = 2 * CDB = 96
quadrilateral ABOC, ang ABO and ACO are perpendicular bc they are tangents, and COB = 96
90 + 90 + 96 + ang A = 360, A = 84