When spelt "too" this means "as well".
He wanted to read but it was too dark.
Yes that is correct. (An easy way of remembering the difference is that you use 'too' when you want to say 'also'. e.g. 'Would you like to come too?')
Yes, because the apostrophe shows the omission of the word 'is' - ('It is too late', which has been shortened to 'It's too late'.)
the word can't is a contraction that combines can and not. It is 'can, too.'
Yes, "not too" is correct to use when you want to imply moderation or limitations, such as "not too hot" or "not too far." It can help convey a sense of balance or constraint in your statement.
No it's not correct. The word "am" only sounds grammatically correct with the pronoun of I
A balance is the correct tool to use to find the mass of an object.
It means it must be grammatically correct. The word spellings and the structure should be correct too.
"alls" is not a standard English word. The correct form would be "all."
Neither really. 'In' would be the word to use.
guess so? i use it too.
Yes, "too" is the correct form to use with "late."