I need to determine if these sentences are statements or not.

1)Abraham Lincoln was the first president of the United States.

2)If Sally calls, tell her I'm at the library.

3)Blondes are more attractive than brunettes.

4) Don't you realize how silly that hat looks?

Three are statements.

Which one is not?

It's #4, since it is a question. As for number 1, I answered no and thought it was a historical fact.

A statement can be a historical fact.

And yes, # 4 is a question.

To determine if the sentences are statements or not, you need to understand the nature of statements. A statement is a sentence that expresses a fact, opinion, or a piece of information. It provides a definite assertion or claim. Let's analyze each sentence to determine if they are statements or not:

1) "Abraham Lincoln was the first president of the United States."
This sentence is a statement because it is expressing a historical fact.

2) "If Sally calls, tell her I'm at the library."
This sentence is not a statement but a conditional sentence. It expresses a hypothetical situation, but it doesn't assert a fact or opinion.

3) "Blondes are more attractive than brunettes."
This sentence is a statement because it expresses an opinion about the attractiveness of different hair colors.

4) "Don't you realize how silly that hat looks?"
This sentence is not a statement but a question. It seeks information or an opinion and doesn't make a direct assertion.

In summary, sentence 1 and 3 are statements, while sentence 2 and 4 are not statements. Remember, when determining if a sentence is a statement or not, you need to identify if it asserts a fact, opinion, or piece of information.