Answer:
[tex]\frac{5}{7} ft[/tex]
Step-by-step explanation:
Really, really easy!
The formula of a rectangular prism is
Volume= (Area of the base) (height)
[tex]V=Ah[/tex]
We can find the height by dividing both sides of the equation by the Area of the base.
That is
[tex]V=Ah\\\\\frac{V}{A}=\frac{Ah}{A} \\\\\frac{V}{A}= h\\\\\frac{\frac{10}{21} }{\frac{2}{3} }=\frac{5}{7} =h\\[/tex]
So the height is 5/7 ft
