September 2000, we paid 
tolars for a liter of heating oil, and May 2004, we paid 
tolars.
By how many percent was the price of heating oil in May 2004 lower than the price in September 2000?
How much tolars will we pay in September 2000 for a full fuel oil in a cube tank with dimensions of 
m, 
m and 
m? Draw a sketch of the tank.
Is 
liters of heating oil sufficient for heating from October 1 to March 15 of the following year, if the daily consumption is 
litres?
would be paid.
