a) = 2017x (1+3) = 2017 x 4 = 8068
b) = 2017 x (1+2017) + 2018 = 2017 x 2018 + 2018 = 2018 x (2017+1) = 2018 x 2018 = 2018^2
c) = 2001 x 25 + 75 x 2001 = 2001 x (25 + 75) = 2001 x 100 = 200100
d) = 2017 x (1 + 2018) - 2019 x 2016 = 2017 x 2019 - 2019 x 2016 = 2019 x (2017 - 2016) = 2019 x 1 = 2019.