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Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

He that is measured at 220° is a reflex angle. the opposite angle is obtuse. find the measure of obtuse .

1) in triangle the, what is the measure of angle t (in degrees)? 2) in triangle bat, the measure of angle b is 66∘, and the measure of angle t is 77∘.what is the measure of the exterior angle at a (in degrees)?