(1) 19
(2) 2000 + 4*4 = 2016
(3)2000
(4) 2016
(5)2016 + 4 = 2020
(6)9
(7)2000 +4*4*2 + 4 = 2036
(8) 2000 + 4*4 + 4 = 2020
(9) 21
(1) 19
(2) 2000 + 4*4 = 2016
(3)2000
(4) 2016
(5)2016 + 4 = 2020
(6)9
(7)2000 +4*4*2 + 4 = 2036
(8) 2000 + 4*4 + 4 = 2020
(9) 21