Something that represent today’s culture ( sum that isn’t tech or social media)

It depends on which culture you're looking at to be honest. But in the current environment, one item that is fairly prevalent is the coronavirus facemask. You could say it symbolically represents the idea of trying to stay safe and it represents a new norm (that many may consider strange since people are used to seeing each other's faces).

180 square centimeters

step-by-step explanation:

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation: