Question 607141
That's a trick question if that's all the information.
For example, suppose I have 40 ft around and 1 foot deep.
40 ft around can be sides of 10-10-10-10
The area is {{{ 10*10 = 100 }}} ft2
Volume = {{{ 100*1 = 100 }}} cubic ft
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But suppose the 40 ft around is 15-5-15-5, then
the area is {{{ 5*15 = 75 }}} ft2
and the volume is {{{ 75*1 = 75 }}} cubic ft
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So, there's no way to answer the question
unless you have more information, like 
the area to be filled is square, etc.