From the graph, read the water level on day 1 and on day 28.<br><br>
Percentage remaining = (Level on day 28 / Level on day 1) × 100%.<br><br>
For part 2, calculate the rate of loss per day from the graph.<br>
Extend the line into September: find the day when the level drops below 100 cm.<br><br>
Final Answer: Read from the graph and compute.