Find the values of x for which the equation cos x = 1 is true

∠aed is formed inside a circle by two intersecting chords. if minor arc bd = 70 and minor arc ac = 180, what is the measure of ∠ aed? a) 45° b) 50° c) 55° d) 60°

Icould really use some with this question.

Olga bought a new skirt that cost $20. sales tax is 5%. how much did olga pay, including sales tax? 7.