Maricow county charges a 4% local fee on all cell phone bills. If a customers bill comes out to 125 what will their bill be including the local fee their bill

Fanny mendelssohn manages all the magazines and paperback books at a local grocery store. she prices many paperbacks to sell at $7.99. the cost to the store is $5.29. what is the markup rate on a paperback book, based on its cost?

Ineed in figuring out this problem.

Solve the triangle. a = 21°, c = 105°, c = 5