SCSS getting array values?

Question

Sass

Greetings!
I googled the sass / scss documentation, but did not find clear answers to my questions.
Let's say we have an array:

$arrayColors: (
        white,
        black,
        green,
        red,
        orange
);

Questions 1:
1.1. How to get the last value of an array?
There is an array loop:

@each $key, $color in $arrayColors {
      .color-#{$key}
      {
        color: $breakpoint;
      }
}

Questions 2:
2.1. How to start iterating over an array from the end?
2.2. If we started iterating over the array from the end, then how can we get the first value of the array?
Thank you!

Answer 1

google things like:
1) sass length
2) sass nth
and here the reverse loop is described blog.ricardofilipe.com/post/reverse-loops-with-sass