Solve for c in the equation b(a-1) = bc/2 pls help

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.

25 ! i need asap! ! ill mark brainliest!

Me its important ! marge runs an ice cream parlor. her speciality is triple chocolate sundaes. she can prepare 1 sundae every 2 minutes, and she earns $1.20 for each sundae she makes . if she just makes sundaes for a single shift of at most 4 hours and at least 2 hours , which function relates her earnings to the number of minutes she works?