Which radical expression in the picture is equivalent to t^5/8?

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Explanation:

The rule we use is

where 'a' is the base, m stays in the role of the exponent, and n plays the role of the root index (eg: n = 3 is a cube root, n = 4 is a fourth root, and so on).

So for instance,

or in this case,

point a is the center of the circle that passes through points e, f, and g and the center of the circle that passes through points x, y, and z.