all u need is here in the pic



Answer:
for problem 1 it is 2nd one
for problem 2 1200 people bought online cause 15*1200= 18000 18000+2500= 20500 so it would be 3rd one 550
then problem 3 would be 4th one 72
Step-by-step explanation:
the problem 2 one is confusing so it might be wrong hope not cross fingers!!!