Answer:
A & D
Explanation:
If you can fit 3 fish in a 9 gallon tank, that means as a point on a line, that would be at (3, 9).
If you write this as a fraction it's 3/9. Simplifying that, you get 1/3. That means 1 fish needs 3 gallons. If you make hat a point on the line, it's (1,3).
Another equivalent fraction would be 6/18. If you multiply the numerator and denominator by 2, 3/9 becomes 6/18.
B & C are not equivalent fractions.