In this verse (Gen 6:14), three terms (גפר, כפר [first time], and כפר [second time]) are interconnected by a single root. They are translated, commonly, with ‘gopher (wood)’, ‘pitch (it)’, and ‘tar’ (or, ‘pitch’, again), respectively.
All of these term have in common the basic ‘to cover’-centered concept (Davidson, Analytical Hebrew and Chaldee Lexicon: “Gen 6. 14 גפר” i[d]. q[uod]. כפר, ‘to cover over’).
From the latter variant כפר (through a consonantal commutation G > K) - with a very good chance - were derived the Greek term κυπάρισσος (cypress) and, consequently, from here, the posterior (?) Latin term cupressus, of identical meaning.
“ […] *The ἁπ. λεγ. gopher is related to כֹּפֵר, resin, and κυπάρισσος; it is no proof to the contrary that in later Hebrew the cypress is called ‘berosh’, for ‘gopher’ belongs to the pre-Hebraic times*.” (Keil&Delitzsch, *Commentary on the Old Testament*)
“[…] *the cypress tree bids fairest to be the wood of which, the ark was made, as Fuller (Miscellan. Sacr. l. 4. c. 5.), Bochart (Phaleg. l. 1. c. 4. col. 22, 23), and others (id. Scheuchzer. Physic. Sacr. vol. 1. p. 35.) have shown; that being nearest to ‘Gopher’ in sound, and being a wood very durable and incorruptible, and fit for shipping. Alexander made a navy of cypress trees in the groves and gardens about Babylon, as Strabo (Geograph, l. 16. p. 510) relates* […]” (John Gill)
Salvatore Garofalo, *La Sacra Bibbia - Antico Testamento - Genesi* (the translation from Italian is mine): “[…] *Bochart glimpses in* [גפר] *the same root of the Greek [term] κυπάρισσος, ‘cypress’. Its wood were used by Phoenicians to build ships, and by Egyptians to make sarcophagus (= akk[adian] giparru)*.”
Jamieson, Fausset & Brown, *Commentary*: “[…] *probably cypress, remarkable for its durability and abounding on the Armenian mountains*.”
To answer your Question # 1, take account that the wood of cypress possesses two main characteristics:
a) it possesses an high stamina to immersions into sea water, since it is naturally impregnated with resin (כֹּפֵר);
b) it is woodworm-proof.
To answer your Question # 2, read, please the following information.
If we accept the abovementioned equivalence גפר = ‘cypress’ we will able to build a remarkable LOGICAL CIRCLE:
1 - The Noah’s Ark (made to resist to the Flood’s rains) was made of cypress.
2 - The cypress, taken as symbolic object, has - at all times - represented death, or mourning from the dead ones, and until today they are decking thousands of graveyards (artofmourning.com asserts: “Cupressus sempervirens, or the ‘Graveyard Cypress’ is one of the oldest classical mourning symbols used in Western and Eastern societies [also in Muslim world] […]. Known as the ‘mournful tree’ by the Greeks and the Romans, the tree was sacred to the Fates and Furies as well as the rulers of the underworld [like Pluto, the classical ruler of the underworld (see, for example the entry ‘Cyprès’ in the Dictionnaire des Symboles, by Jean Chevalier and Alain Gheerbrant)]. […] Here, there is a great continuity of usage for the tree, as despite its cultural interchange it still remains understood for the same purposes in death.”).
3 - The very important Holiday for the Dead, related strictly to the All Saints’ Day/Halloween, falls on the identical year period of the start of Flood’s rains (some reference works: The Worship of the Dead, by J. Garnier, 1904, London, e.g. Chapt. 1 pages 3-11; along with the following WEBlink htpps://aroyking.wordpress.com/2009/10/31/the-connection-between-halloween-and-the-great-flood/)
“Come away, come away, death,
And in sad cypress let me be laid.”
(William Shakespeare, The Twelfth Night, Act 2, Scene 4)
So, the wheel has come…