Party Pals Company received an invoice dated Oct $18,2023,$ for $$7,800$ with trade discount series of $25\%$ and $15\%.$ Payment terms are $5/10,2/30,$ n$/60.$

a$)$ What is the invoice amount?

b$)$ What are the last days of the two discount periods?

c$)$ How much should be paid on Oct $26$ to reduce the unpaid balance to $$3,000\mathrm{.}00?$

d$)$ How much should be paid on Nov $10$ to reduce the unpaid balance by $$1,500\mathrm{.}00?$

e$)$ What was the account balance on after the Nov $10$ payment?