Am i dealing with harmonic stuff (trig)?

Percent increase and decrease. original number: 45 new number: 18

Will mark the brainliest.paula makes stained-glass windows and sells them to boutique stores. if her costs total $12,000 per year plus $4 per window for the frame. how many windows must she produce to earn a profit of at least $48,000 in one year if she sells the windows for $28 each?

Find all the angles that satisfy the equation cos(θ)=32