Answer: 9/4a^2|b^3|c^4
Explanation:
81/16
Square root(81) = 9
Square root(16) = 4
9/4
Since 4 is the index of the radical, all of the exponents divide by 4
(index 4)a^8 = a^2
(index 4)b^12 = b^3
(index 4)c^16 = c^4
Now put the variables together to get the answer:
9/4a^2|b^3|c^4