How do you calculate cash collection for just june?

Month Sales $ Month Sales $ Jan Feb Mar Apr May June 12479 July 18704 Aug 43708 sep 18552 Oct 12479 Nov 18704 Dec 18552 43708 12479 43708 18704 18552 Sales are collected as follows: In the month of Sales: 31% In the next month: 31% After 2 months: 7% Remainder is considered as bad debt and is not collected. Calculate the cash collection for June.