A retailer received an invoice dated 21 February 2015 worth $4,350 of goods that included a prepaid freight cost of $30. The invoice was offered trade discounts of 8% and 5% and cash discount term of 4/15, 2/20, n/30.

Question

A retailer received an invoice dated 21 February 2015 worth $4,350 of goods that included a prepaid freight cost of $30. The invoice was offered trade discounts of 8% and 5% and cash discount term of 4/15, 2/20, n/30. 
(a) Find the last date to settle the invoice. 
(b) Assume that the retailer paid $400 on 7 March 2015 and the balance on 14 March 2015. Find the amount of the balance that was paid.