84 a positive integer is divisible by 9 iff the sum of the digits in jts decimal representation is divisible by: (a) 3 9 (c) 81 (d) none o 8 p is n prime and a

84 A positive integer is divisible by 9 iff the sum of the digits in jts decimal representation is divisible by: (A) 3 9 (C) 81 (D) None o 8 p Is n prime and a be any integer such that pta, Then the solution or n congruence ax b(mod p) is given by (A) xa mod p (B) xp mod a (C) x-a mod p (D) None of these 86. The integer p is prime if and only if: LP-1--D(mod p) (C)1p-1- #1 (mod p) B) P-1 1(mod p) (D) None of these 8 L.etp be a e nd n be uny . integer, then -1"(mod p). p np (A) peime, positive (B) odd, positive (C) odd, negative (D) None of these 88. The quadratic congruence x -l(mod pl. p is a has a solution iff p-1(mod4). (A) composite (B) prime (C) perfect (D) None of these 89, Ifnis not divisible by any prime S Vn, then n is a'an. (A) Even (B) Odd (C) Prime (D) None of these (16) FIH3-MA7/8)8