So for exercise 4, I used a couple of tact switches that I had already plugged into the the breadboard, a messy array of wires, 2 LEDs, a bunch of resistors and a Light Dependant Resistor (LDR). (There are a whole bunch of other random components attached to the board that do absolutely nothing).
The code is a single file, but you can swap out the various parts in loop().
Arduino Sketch: MTI_EX_4
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