Describe the following set in Roster form : (i) {x:x is a letter before e in the English alphabet}. (ii) {x∈N : x^2 less than 25}. (iii) {x∈N : x is a prime number, 10 less than x less than 20}. (iv) {x∈N : x = 2n, n∈N}. (v) {x∈R:x greater than x}. (vi) {x:x is a prime number which is a divisor of 60}. (vii) {x: x is a two digit number such that the sum of its digits is 8). (viii) The set of all letters in the word ‘Trigonometry’. (ix) The set of all letters in the word ‘Better’.