HEY can some please help me I will give you BRAINLEST!!
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Answer:
11 cm
Step-by-step explanation:
Length of the diagonal
[tex] = \sqrt{ {8}^{2} + {6}^{2} + {5}^{2} } \\ = \sqrt{64 + 36 + 25} \\ = \sqrt{125} \\ = 11.1803399 \\ \approx \: 11 \: cm[/tex]