Let A = {ϕ, {ϕ}, 1, {1, ϕ}, 2}. Which of the following are true?

(i) ϕ A


(ii) {ϕ} A


(iii) {1} A


(iv) {2, ϕ} A


(v) 2 A


(vi) {2, {1}} A


(vii) {{2}, {1}} ⊄ A


(viii) {ϕ, {ϕ}, {1, ϕ}} A


(ix) {{ϕ}} A.

(i) True


Φ is a member of set A. Hence, true.


(ii) True


{ Φ} is a member of set A. Hence, true.


(iii) False


1 alone is not a member of A. Hence, false.


(iv) False


We can see that 2 is a member of set A, {2, Φ} is not. Hence, false


(v) True


2 is a member of set A. Hence, true.


(vi) True


{1} is not a member of set A.


(vii) True


Neither {2} and nor {1} is a member of set A. Hence, true.


(viii) True


All three are members of set A. Hence, true.


(ix) False


{{ϕ}} is not a member of set A. Hence, false.


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