Alright, let's work through 7989 times 5005 step by step
7989 × 5005 = 5005 × (7989)
+ 5005 × 9 yielding 45045
+ 5005 × 80 yielding 400400
+ 5005 × 900 which equals 4504500
+ 5005 × 7000 producing 35035000

= 39984945
