1. Corrigan Health Center provides a variety of medical services. Cash collections for July, August and Sept. were $99,000, $156,000, $120,000. Cash payments were $145,000, $101,000 and $ 137,000 respectively. The cash balance at 7/1 was $31,000. They must maintain a minimum of $24,000 in cash at the end of every month to comply with loan requirements. How much money did they have to borrow during the months of July, August and Sept in total?

   	a.	$39,000
   	b.	$46,000
   	c.	$ 31,000
   	d.	$17,000