Answer:
7/4 or 1.75 drops
Explanation:
In one gallon there are 128 ounces, if it takes 28 drops of coloring to turn 128 ounces of milk green then:
28/128
7/32
it takes 7/32 drops of food coloring to turn one ounce of milk green.
for 8 ounces, you multiply it by 8:
8*7/32
7/4≈1.75
∴ It would take 1.75 or 7/4 drops of coloring to turn 8 ounces of milk green.