how much soil?

[EngTeach]

I built a small retaining wall acress the back of my property and would like to fill it it in for planting. It is 23 feet x 18 inches and about 8 inches high. How much soil do I need to fill it in?

Tracy

[sir.prize]

How to calculate . . .

http://msucares.com/news/print/sgnews/sg97/sg9 70327.htm

[MustafaTickl]

.65 of a cubic metre.

[EngTeach]

Thanks very much!!!!