Answer:
not 100% about this answer but I think it is the 8oz bottle
Explanation:
take $1.36 and divide it by 8 which gives you .17 which is 17 cents per oz now do the same thing for the 16 oz so take $3.20 and divide it by 16 and you get .2 which is 20 cents per oz so the 8oz has the lowest unit price of the two!