For a experiment, Jenna needs to make a dilute solution that is 10 ounces of 40% acid. But Jenna only has solutions that are 30% acid and 70% acid. How many ounces of 70% acid solutions should she use?
A. 2.5 ounces
B. 5 ounces
C. 7.5 ounces
D. 8 ounces
Not sure if I would times the ounces with the acid.