Explanation:
A proposition is a statement that can be either true or false, but not both. Let's analyze each of the given expressions:
a) "Do not pass go." - This is not a proposition because it is a command or an imperative statement, not a declarative statement that can be true or false.
b) "What time is it?" - This is not a proposition because it is a question and does not make a declarative statement with a truth value.
c) "There are no black flies in Maine." - This is a proposition. Its truth value depends on whether there are indeed no black flies in Maine at a given time or place. It can be either true or false.
d) "4×=5" - This is a mathematical equation, not a proposition. It can be true or false depending on the values of x, but it is not a declarative statement itself.
e) "The moon is made of green cheese." - This is a proposition. In reality, it is false because the moon is not made of green cheese. So, the truth value of this proposition is false.
f) "2n>100." - This is a mathematical inequality, not a proposition. It can be true or false depending on the value of n, but it is not a declarative statement itself.
So, the propositions in the given list are:
c) "There are no black flies in Maine." (truth value depends on the situation)
e) "The moon is made of green cheese." (false)