Find the selling price of a $450 painting with a 45% markup

Solve the equation x/4 - 5= -8 -27 -12 -7 12

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)?

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.