An algebraic expression is an expression that includes constants, variables, and the algebraic operations (add, subtract, multiply, divide.
Answer: 100 ml each hour.
Step-by-step explanation:
1000 -400 =600 used from original amount.
Divide 600/6 = 100 ml per hour.
Well maybe because the only thing that is different is the - and +
The answer is

i hope this answer helps you!
I cant answer if i dont know what math would you mind telling me what math