PLZZ HELPP IM FAILLING THIS CLASS

Answer:
Hope this helps!!! :)
Step-by-step explanation:
#1: if there is buy 1 get 1 free, then buy 6 get 3 free. so 2.8 times 3 = $8.4
#2: 4 for $3. break it up to 1 for $0.75. now 0.75 times 6 = $4.5
#3: the second one. $4.5 < $8.4
#4: 45 times 12 = $54