Determine x where x is the least non-negative residue modulo n in the following:
(a) $100 ≡ x \pmod{12}$
(b) $666 ≡ x \pmod{11}$
(c) $−5 ≡ x \pmod{15}$
(d) $1000 ≡ x \pmod{1001}$
(e) $−25 ≡ x \pmod{7}$
(f) $−100 ≡ x \pmod{24}$
(a) $x = 4$
(b) $x = 6$
(c) $x = 10$
(d) $x = 1000$
(e) $x = 3$
(f) $x= 20$