WILL GIVE BRAINLIEST !!! AND 75 POINTS
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Answer:
[tex]\Large \boxed{\sf 12.6}[/tex]
Step-by-step explanation:
The diameter of the base is 8 so radius is 8/2 = 4
Use Pythagorean Theorem to find hypotenuse of the right triangle
[tex]\displaystyle c=\sqrt{4^2+12^2} =12.6[/tex]