Borei pri ha'etz: for all fruit that grows on trees. An apple tree is a tree, so ha'etz applies.
Question 2
What blessing covers meat, fish, water, and eggs?
Shehakol nihyeh bidvaro — the universal blessing for anything that doesn't fit into a more specific category. Meat, fish, water, eggs, mushrooms, etc.
Question 3
You're eating a soup where vegetables are the main ingredient and there are a few croutons. What blessing?
Ikar v'tofel: the primary ingredient determines the blessing. Croutons as a minor garnish don't override the soup's vegetable-based blessing.
Question 4
You're taking an herbal remedy and must swallow it with something sweet. What blessing on the sweet?
Eating for medicinal rather than enjoyment purposes: Shehakol applies. The blessing reflects your relationship with the food — medicine, not pleasure.
Question 5
What is the blessing hierarchy principle when you're unsure which blessing applies?
Shehakol — "by whose word all things exist" — is the universal fallback. If you say Shehakol over something that needed Ha'etz, you've fulfilled the obligation (though not ideally).