# 7.6: Exercises

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1. Implement the 2-to-4 decoder using 7404 (NOT) and 7808 (AND) chips on your breadboard.
2. Implement the 2-to-4 decoder circuit with a 74139 chip on your breadboard.
3. Implement a 1-to-2 decoder in Logisim. Implement this circuit on your breadboard.
4. Implement a 3-to-8 decoder using NOT and AND gates in Logisim. Show that it is correct by showing it generates the same output as a 3-to-8 Decoder found in the Plexors menu of Logisim.
5. In Logisim, implement a 3-to-8 decoder using two 2-to-4 decoders, and as many AND gates as you need. Compare the total number of AND gates in the circuit to the number of AND gates used to implement the 3-to-8 decoder with 2-input AND gates in question 4. Which circuit do you think is faster?