Which of the following collections are sets? Justify your answer:
Collection of all rectangles in a given plane.

Which of the following are sets ? Justify your answer. The collection of all even integers.

Which of the following are sets ? Justify your answer. The collection of all boys in your class.

Which of the following are sets ? Justify your answer. The collection of questions in this Chapter.

Which of the following are sets ? Justify your answer. The collection of all natural numbers less than 100.

Which of the following expressions are polynomials? Justify your answer: 8?

Which of the following are sets ? Justify your answer. A collection of most dangerous animals of the world.

Which of the following are sets ? Justify your answer. The collection of all the months of a year beginning with the letter J.

Which of the following expressions are polynomials? Justify your answer: 1/(2x)

Which of the following expressions are polynomials? Justify your answer: 1-sqrt5x

Which of the following are sets ? Justify your answer. A collection of novels written by the writer Munshi Prem Chand.