Identify the following sets as null set or singleton set.
D = The set of all triangles having four sides.

Identify the following sets as null set or singleton set. C = {0}.

Identify the following sets as null set or singleton set. B = The set of all even natural numbers which are not divisible by 2.

Identify the following sets as null set or singleton set. A = {x:x inNN,1ltxlt2}

Which of the following is a null set

Which of the following is a null set ?