√28 x √7 x2 = ?

1. 14
2. 24
3. 28
4. 7

√28 x √7 x 2 = √7 x √4 x √7 x 2
                              ​=  √7 x 2 x √7 x 2
                              = √7 x √7 x 2 x 2
                              ​=     7 x 4
                              ​=      28

Option 3) 28 is the correct answer.​
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