Find the Mass of the Surface S Having the Given $x ^ { 2 } + y ^ { 2 } + z ^ { 2 } = 9$

question 69

Multiple Choice

Find the mass of the surface S having the given mass density. S is the hemisphere $x ^ { 2 } + y ^ { 2 } + z ^ { 2 } = 9$ , $z \geq 0$ ; the density at a point P on S is equal to the distance between P and the xy-plane.

• A) \(9 \pi\)
• B) \(27 \pi\)
• C) 9
• D) \(3 \pi\)

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Definitions:

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