SOLUTION
The equation relating x and y is

The equation connecting x and y is an equation of the form

Since slope is also refers to as changes between two variables,
Hence
Cmparing with the equation given,

Therefore,
The change per minute in the total amount of water in the pond is 27 litres
The starting amount ot water is when the time is at 0 minutes .
Hence, substite x=0 into the equation given and obtain the value of y which stands for the amount of water at the begining.

Therefore,
The starting amount of water is 600 litres
Answer: A) 27 litres B). 600 litres