I NEED HeLPn PLS PLS PLS

Will mark brainliest for correct answer! i have been on this problem for an hour and can't find the answer. i'm begging here! incase you cant read the instructions in the picture because of too much or too little lighting: note: enter your answer and show all the steps that you use to solve this problem in the space provided.write a list of steps that are needed to find the measure of b. provide all steps as clear as possible, !

Megan is making bracelets to sell to earn money for the local animal shelter. it takes her 1/4 hour to pick out all the beads and 1/10 hour to string them.this week, she only has 5 1/4 hours to make bracelets. how many bracelets will megan be able to make?

I'm confused on how to solve the triangle. can someone me ?