Express amount in rands

$1\mathrm{.}2\mathrm{.}1$ calculate the profit that super stores would make if the account is settled in $15$ days time.

$1\mathrm{.}2\mathrm{.}2$ Should the customer fail to pay the amount due and the account is written off after $90$ days $,$ how much would be the loss to Super stores?

Information

Super stores intends selling a dishwasher on credit. The selliprice of the dishwasher is R$7000.$ The dishwasher is priced at cost plus $40\%.$ Credit terms of $4/15$ net days were agreed upon. The cost of capital is $18\%.$