The answers are : A and C
Answer: The volume of largest rectangular box is 4.5 units.
Step-by-step explanation:
Since we have given that
Volume = 
with subject to 
So, let 
So, Volume becomes,

Partially derivative wrt x and y we get that

By solving these two equations, we get that

So, 
So, Volume of largest rectangular box would be

Hence, the volume of largest rectangular box is 4.5 units.
The answer is b. 2,8 and 3,11
8=3(2)+2
8=6+2
8=8
11=3(3)+2
11=9+2
11=11