How do you solve for x, y,and z? In a triangle

Can someone show me step by step how to do this?

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

Carmen and matt are conducting different chemistry experiments in school. in both experiments, each student starts with an initial amount of water in a flask. they combine two chemicals which react to produce more water. carmen's experiment starts with 30 milliliters of water in a flask, and the water increases in volume by 8.5 milliliters per second. matt's experiment starts with 10 milliliters of water and increases in volume by 28% each second.