Can someone explain what Order of Magnitude is? NO GOOGLE SEARCHES PLZ

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?

If f(x) = 2x + 8 and g(x) = x4, what is (gº)?

When is g(x) = 0 for the function g(x) = 5.23x + 4?