Group Problem $5$: The Duquesne Company has the following transactions during April $2023$:

$$ Cash sales to customers totaling $$14,700.$

$$ Credit card sales to customers totaling $$29,500.$ The credit card fee to the merchant is $3\mathrm{.}0\%.$ The credit card companies have paid all amounts due for April.

$$ A $$5,000$ sale on account to a long$-$time customer with terms of $2/10,$ n$/30.$ The sale is made on April $7.$ The customer pays the invoice on April $15.$

$$ A customer returns product they had purchased last month for $$750.$ Duquesne accepts the return and gives the customer a cash refund.

Calculate the following amounts:

a$.$ Service credit card expense fee