need help with this one

Falak receives an invoice from MTZ Equipment and Storage dated December 5th, 2012 for $1,130 with terms 6/9, 1/12, n/30. This invoice was paid on December 19th, 2012. Round the answers to parts a. and b. to the nearest cent if necessary. a. How many days were there between the date of the invoice, and when the invoice was paid? Number of days = days b. How much was the amount of the discount? Amount of discount = c. How much was paid? Amount paid =