To my knowledge, the proper capitalization is The United States of America. However, when using the letters only, it is the US or the USA.
Yes, you should capitalize the word "Figure" when referring to a figure in a paper.
Yes, you capitalize the word "Chapter" when referring to a specific section in a book.
When referring to the fish, it shouldn't be capitalized.
Yes.
Yes, you should capitalize "French" when referring to a French language class as it is a proper noun.
Yes, the word "Marine" should be capitalized when referring to a member of the US Marine Corps or to anything related to the Marine Corps.
First of all, 'CPA' is not a word. If you're referring to 'Certified Public Accountant', then yes, you would capitalize 'CPA'.
Only if you are referring to God.
No. It's not necessary.
Capitalize the word "legislature" when you are referring to a specific legislative body, such as the United States Congress or the Canadian Parliament. If you are referring to legislatures in a general sense, then you do not need to capitalize the word.
Only if you are referring to a specific honor roll.
Yes u do