I believe זאת and זה can only be used as demonstrative pronouns (replacing a noun)... "THIS is a long road."
Unlike English, Hebrew has a different form for demonstrative adjectives (when it's modifying a noun rather than replacing it.) Which road? THIS road is long.
I'm patiently waiting for Duo to get around to demonstrative adjectives... All the outside sources I can find are for Biblical Hebrew, and I'm afraid of misleading myself with out-dated grammar. ;-)
Yes, ארוכה is "aruka". But note that ארוך is "arokh". There are several adjectives that act in a similar manner - "o" in the masculine and "u" in the feminine. For example "red" אדום (adom - m) and אדומה (aduma - f). There is also one other example I can think of, where the letter changes its pronunciation, like here - "yellow" צהוב (tzahov - m) and צהובה (tzehuba - f)
How do you pronounce "ך" at the end of a word? I thought it was always pronounced like the English "k" at the beginning and ends of words, but here it sounds more like the "ch" in "loch" and "Bach".
I don't know if I'm mishearing, or if different words are pronounced differently, or if there's a rule I don't know that may or may not depend on neighboring words.
The letter כ or ך is called kaf/chaf and is pronounced each way, depending on grammar/syntax. כ is sometimes pronounced k and sometimes ch as in Bach.
Most often, but not always, at the beginning of a word it is k. I can't think of a time ך (final chaf) is pronounced k, I can only think of ch at the end of a word. In the middle of a word it is usually ch, but it can be k.
When Hebrew is written with full nikkudot, you can tell which way to pronounce it: with a dot in the middle (called a dagesh) it is k, and without a dot, ch.