Not sure how to solve this

Which of the following is the explicit rule for a geometric sequence defined a recursive formula of a -5a for which the first term is 23?

The answer is 7.2 how would you put this as money

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?