The receiver should be 0.4 feets above the vertex
The distance from the vertex, p is defined as :
[tex]p = \frac{ {x}^{2} }{4y} [/tex]
Where,
y = depth
x = radius
[tex]radius \: = \frac{diameter}{2} [/tex]
[tex]x = \frac{2.4}{2} = 1.2[/tex]
Therefore,
[tex]p \: = \frac{ {1.2}^{2} }{4(0.9)} = \frac{1.44}{3.6} =0.4[/tex]
Hence, the receiver should be 0.4 feet above the vertex.
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