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If $$\overrightarrow {\text{r}} $$ is the position vector of any point on a closed surface S that encloses volume V then $$\iint\limits_{\text{S}} {\overrightarrow {\text{r}} \cdot {\text{d}}\overrightarrow {\text{S}} }$$  is equal to

If $$\overrightarrow {\text{r}} $$ is the position vector of any point on a closed surface S that encloses volume V then $$\iint\limits_{\text{S}} {\overrightarrow {\text{r}} \cdot {\text{d}}\overrightarrow {\text{S}} }$$  is equal to Correct Answer 3V

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