PLS HELP NEEDED TODAY

What is the value of the expression below? (81^2)^1/8

Arefrigeration system at your company uses temperature sensors fixed to read celsius (°c) values, but the system operators in your control room understand only the fahrenheit scale. you have been asked to make a fahrenheit (°f) label for the high temperature alarm, which is set to ring whenever the system temperature rises above –10°c. what fahrenheit value should you write on the label

The ph level of a blueberry is 3.1 what is the hydrogen-ion concentration [h+] for the blueberry