You would capitalize "Juicy Lucy's" and possibly "Truck Stop" if it is part of the official name.
In "Yours truly," you capitalize the first letter of each word if you are using it as a complimentary close in a letter, as it is a formal sign-off.
No, "sign language" is not typically capitalized in a sentence unless it is part of a title or at the beginning of a sentence.
It's appropriate to capitalize "Friend" as a sign of respect when closing a letter. For example: "Sincerely yours, Your Friend."
No, abbreviated letters should be capitalised. Two examples are: the USA not Usa; the UK not Uk. At one time, each letter would have a full stop in between: U.S.A. or U.K. but the full stops are often omitted nowadays.
No.
At the beginning of a sentence, after a full stop or at the start of a new paragraph.
No, only after a full stop (period). Also do not capitalise "The" and "A" in your sentence.
A full stop.
As long as it takes to make a full stop and viewing that it is safe to pull out.
It can be
you must come to a full stop only
Red Stop Light Flashing Red Stop Light Red Stop Sign
You would capitalize "Juicy Lucy's" and possibly "Truck Stop" if it is part of the official name.
In "Yours truly," you capitalize the first letter of each word if you are using it as a complimentary close in a letter, as it is a formal sign-off.
The rule is to stop behind the stop sign. If there is a white line on the road, the vehicle should be completely behind it. Once you have come to a full stop, you may have to creep forward to see safely.
You ALWAYS use a fullstop, unless you are ending the sentence with another punctuation mark. If the sentence is a question, then you'd end the sentence with a question mark. You would not add a full stop after the question mark. eg. How many minutes are there in an hour? If you use an exclamation mark, then you do not add a full stop. eg. Watch out!