Answer:
a) +16 gallons
b) -3 fish
Step-by-step explanation:
a) 2 gallons a day * 8 days means that 16 gallons of water is pumped into the pool. This is an increase so is positive.
b) 21 fish removed in total can be divided by the 7 days to give 3 fish a day because the number of fish removed each day is the same. This is fish removed, so is a decrease and is negative.
