The answer is 7.46 , so when rounded, the answer is B
Each bottle costs seven dollars. Two of them would cost $14 and three would cost $21. Buying three bottles, the amount is $21 which exceeds $16. Therefore, a $5 discount will be given. Subtracting $5 from the $21 will give $16. You have just enough amount to buy THREE bottles of olive oil.
3 -1i + 21i -7i2 now you have to fix the last factore because you have to change the imaginery i this would give you the answer of 3 - 1i + 21i +7 now add common factor which would give you the final answer of 3 +20i +7