Answer:
1875
Step-by-step explanation:
3x5 = 15
15x 5 = 75
75x 5 = 375
375 x 5 = 1875
1875 because at the end of the next week, which basically turns 8 weeks into 4, and the number of contaminants multiply by 5 each other week.
Complementary: (2,3) & (1,9)
Supplementary: (6,7) & (5,8)
3
Absolute value = 5
Absolute valve of a number is always positive regardless of direction.