Describe the following sets in Roster form :
(i) {x : x is a letter before e in the English alphabet}.
(ii) {x ϵ N:x2<25}
(iii) {x ϵ N: x is a prime number, 10 < x < 20}.
Which of the following letters of the English alphabet have reflection symmetry about a vertical mirror?
Which of the following sets are finite and which are infinite ?
(i) Set of concentric circles in a plane.
(ii) Set of letter of the English Alphabets.
(iii) {x ϵ N;x>5}