Only if they are at the start of a sentence. Otherwise they are not capitalised.
Yes it should always be capitalized.
No. It is a proper noun which means that it should always be capitalized. You should always right it as Buckingham Palace.
Yes, "I am" is typically capitalized because "I" is a pronoun and should always be capitalized in English.
No it should not, unless it's used at the beginning of a sentence. It's just a common noun, not a real noun, so no different from 'car', or 'banana'.
Yes, when referring to the title of the President of the United States, it should always be capitalized.
Yes, both Hindu and Hinduism should always be capitalized.
When it refers to the language, it should always be capitalized.
Only if they are at the start of a sentence. Otherwise they are not capitalised.
It is a proper noun, and thus should be capitalized.
Yes, it should always be capitalized.
Yes, “Arctic” should be capitalized when referring to the region around the North Pole. The Arctic is a proper noun and should always be capitalized.
No, the word "rif" is not always capitalized. It should only be capitalized if it is part of a proper noun or at the beginning of a sentence.