Answer:
B. 0.06 ounce
Step-by-step explanation:
The mixture prepared by Chuck is enough for 14 plants.
If Chuck only used it, according to the recommended amount, for 12 plants, then only 12/14 parts of the 0.42 ounces of plant food were used and 2/14 parts still remain the watering can. The amount of plant food left, in ounces, is:
[tex]F=0.42*\frac{2}{14}\\ F=0.06\ ounce[/tex]
0.06 ounce is left in the watering can.