For question one, he still owes his uncle $10 because he only payed him $200. So no it is not settled.
(sorry dont have much time to do #2)
#3) Archibald payed off $200 of his debt only to have $10 left over to pay. $200-$210=-10
#4) Archibald was in debt by $210, he eventually earned $200 and payed off his debt, but still had -10 left over that he has to pay.