Chander Bookstore, is a student co$-$op$.$ Chander Bookstore uses a perpetual inventory system. The following transactions $($summarized$)$ have been selected for analysis:

a$.$ Sold merchandise for cash $($cost of merchandise $$170,270).$$ $310,750$b$.$ Received merchandise returned by customers as unsatisfactory $($but in perfect condition$)$ for cash refund $($original cost of merchandise $$652)\mathrm{.}1,710$c$.$ Sold merchandise $($costing $$10,170)$ to a customer on account with terms n$/30\mathrm{.}22,600$d$.$ Collected half of the balance owed by the customer in $($c$)\mathrm{.}11,300$e$.$ Granted a partial allowance relating to credit sales the customer in $($c$)$ had not yet paid$\mathrm{.}1,360$f$.$ Anticipate further returns of merchandise $($costing $$226)$ after month$-$end from sales made during the month$\mathrm{.}830$

Required:

$2.$ Compute the gross profit percentage.