The last part of a letter is the signature.
Countries beginning and ending with the letter A are:AlgeriaArgentinaAlbaniaAndorraArmeniaAustraliaAustria
7-letter words ending with H:anguishbeneathbeseechblemishboorishbrutishcherisheyelashfurnishgarnishimpeachmannishmenorahnourishpiggishprudishreddishrematchscratchselfishstealthsunfishtarnishunearthunleashunlatchvarnishwarpath
Some five letter words ending in AT are:bleatbloatcaratcheatcleatfloatgloatpleatsplatsquatsweattreatwheat
There are no English 4-letter words ending with 'has'.
Some six letter words ending in I are:alkalialumnibanzaibikinikabukipirogisafariscampiwasabi
Technically, "epistle" means a letter. The ending of a letter is usually called a "closure," which is simply a polite and accepted form of ending a letter. For example: "Sincerely yours, XYZ"
valediction
viper
BLOC
suffix
titled
covey
There is a city in Utah called Tropic.
covey (quail)
the signature of a letter is called the complimentary close or ending
The ending may include a "Complimentary close" such as Very truly yours, Cordially, Sincerely, etc. The "Signature" would follow the close.
Countries beginning and ending with the letter A are:AlgeriaArgentinaAlbaniaAndorraArmeniaAustraliaAustria