Answer:

Step-by-step explanation:
The fish population after t years can be modeled by the following equation:

In which F(0) is the initial population and r is the constant rate of decay.
Year one the fish population was 18000
This means that 
In year three the fish population was 8000 fish.
Two years later, so 






So

Slope is rise/run
to find it we do (y1-y2)/(x1-x2)
y1 means the 1st y and y2 means the second y
in (x,y) form
y1=4
y2=4
x1=10
x2=7
(4-4)/(10-7)=0/3=0
slope is 0
Answer: 140 m3
Step-by-step explanation:
Multiply the area of the trapezoid face by the length .
Since the area is 20, you multiply it by 7 to get 140
2.5 gallons is divided among 10 people.
2.5/10=0.25 gallons