The causes of climate change can be divided into two categories: natural and human causes. The natural variation of the climate has always been part of earths history. it is noe a great concern that the climatic changes occurring today may be the direct result of mans activities. ALL BUT ONE is a natural cause of climate change.

A- ocean currents
B- volcanic eruptions
C- Earths orbital changes
D- increased greenhouse gases

D- increased greenhouse gasses

well done that is correct but this isn't maths its science

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:

the answer is c 150

step-by-step explanation: