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[tex] \frac{ \sqrt{28} }{2} [/tex]
We know that √4 = 2
Therefore, [tex]\boxed {Option \ A \ is \ one \ right \ answer } [/tex]
Breaking √28, the factors of 28 are 4 and 7, 2 and 14. In these the first pair has a perfect square root
So, [tex]\boxed { \frac{ (\sqrt{4})( \sqrt{7}) }{2} } = \boxed { \frac{2 \sqrt{7} }{2} } [/tex]
2 and 2 cancels out leaving us with √7
Which means, [tex]\boxed { Option \ D \ is \ another\ answer } [/tex]