A client owed an accountant $$2,500$ for an accounting service provided. The client believed that the services the accourtant provided cost less than $$2,500$ because they did not seem difficult, based on the client's judgment. When the accountant demanded payment, the client sent a check for $$2\mathrm{.}250$ marked thendered in full satisfaction." The accountant endorsed and cashed the check.

Which typo of settlement agreement is this?