Proposal new exercise in the Resistor series: Resistor Color Trio

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About the series #1458
This is # 3 in the Resistor Series. It is a follow up for Resistor Colors Duo
This exercises introduces the third color band, that is needed to find the real value of a resistor.

Description

If you want to build something using a Raspberry Pi, you'll probably use resistors. For this exercise, you need to know only three things about them:

• Each resistor has a resistance value.

• Resistors are small - so small in fact that if you printed the resistance value on them, it would be hard to read.
  To get around this problem, manufacturers print color-coded bands onto the resistors to denote their resistance values.

• Each band acts as a digit of a number. For example, if they printed a brown band (value 1) followed by a green band (value 5), it would translate to the number 15.
  In this exercise, you are going to create a helpful program so that you don't have to remember the values of the bands. The program will take 3 colors as input, and outputs the correct value, in Ohms.
  The color bands are encoded as follows:

• Black: 0

• Brown: 1

• Red: 2

• Orange: 3

• Yellow: 4

• Green: 5

• Blue: 6

• Violet: 7

• Grey: 8

• White: 9

In Resistor Colors Duo you de-coded the first two colors. For instance: orange-orange got the main value 33
The third color stands for how many zeros need to be added to the main value. The main value plus the zeros gives us a value in Ohms.
For the exercise it doesn't matter what Ohms really are.
For example:

• orange-orange-black would be 33 and no zeros, which becomes 33 Ohms
• orange-orange-red would be 33 and 2 zeros, which becomes 3300 Ohms
• orange-orange-orange would be 33 and 3 zeros, which becomes 33000 Ohms.

(If Math is your thing, you may want to think of the zeros as exponents of 10. If Math is not your thing, go with the zeros. It really is the same thing, just in plain English instead of Math lingo.)

This exercise is about translating the colors into a sentence:

"The value of this resistor is … Ohms."

So an input of “orange”, “orange”, “black” should return

“The value of this resistor is 33 Ohms.”

The trick is that when we talk about Ohms, as soon as we get more than a thousand, we say “kilo”, in the same way that we say “kilograms” (kg) and “kilometers” (km). In the same way, we get “kilo-ohms” (kOhms).
So an input of "orange", "orange", "orange" should return

"The value of this resistor is 33 kOhms."

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Question to track maintainers:
In the description, we reference the previous exercise in the series. That's because we think it makes sense to have the Duo and Trio exercises both in the track. Is our thinking correct? Or do you see reasons to add only Trio and not Duo?

If maintainers choose to only implement the Trio exercise, we should adjust the description, to include how to compose the main value by using the first two color bands.