Answer:
<u>B.(-5.5; 0)</u>
Step-by-step explanation:
Answer: the answer is 2
The two 50ml bottles
(I will be using the $ but just change the sign to the euros)
$55/80ml= .68 per ml
45+22.5= $67.5
67.5/100 is about $.67
Therefor the two 50ml bottles is cheaper per ML and you get more product
, or 
. Plugging in our value 9 for 
, we get 
.