Ristorante Italiano made payments of $5000 on March 29 and $3000 on April 7 to General Restaurant

Question:

Ristorante Italiano made payments of $5000 on March 29 and $3000 on April 7 to General Restaurant Supplies on an invoice for $11,870. The invoice was dated March 21 and carried terms of 11/2 /10, ½ /10, n/30.
a. What is the balance after the second payment?
b. On what date is the balance due?