Answer:

Step-by-step explanation:
The correct question should be:
We have been told that all we have to do to get profit is to subtract the cost from revenue.
Revenue = 
Cost <em>= </em>
<em />
<em />
Hence:
Profit = 

Putting it in ordered form:

This is an expression for the profit.
Answer:
c is the correct answer
Step-by-step explanation:
because i worked it out
0.5a - 0.3 = 5
Add 0.3 to both sides:
0.5a = 5.3
Divide both sides by 0.5:
a = 10.6
3.250 liters of softener because you have to jump three times according to the ladder method.