2. Which of these are propositions? What are the truth values of those that are propositions?
a)Do not pass go.
b)What time is it?
c)There are no black flies in Maine.
d)4 + x = 5.
e)x + 1 = 5 if x = 1.
f)x + y = y + z if x = z.
Propositions are investigated. The response received a rating of "5/5" from the student who originally posted the question.