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1. The full adder is usually a component in a cascade of adders, which add 8, 16, 32, etc. bit binary numbers. The circuit produces a _______________

eight bit (byte) output

two-bit output

one-bit output

output that is always 'high' or 1

2. A full adder is a logical circuit that performs an addition operation on three one-bit binary numbers. The full adder produces a sum of the three inputs and carry value

TRUE

FALSE

3. A full adder can be combined with other full adders or work on its own.

FALSE

TRUE

three inputs and two outputs.

a single input and a single output

multiple (up to 3 billion) inputs and a single output

two inputs and one output

5. Full adder: The first two inputs are A and B and the third input is an input carry that is sometimes designated as CIN

TRUE

FALSE

6. In the following truth table for a full adder, the CIN and COUT stand for: CIN = 1 and COUNT = CIN + 1

total carry count (for inputs) and total count + 1

CIN = input carry and COUT = output + CIN

input carry and output carry

7. Analyse the following diagram for a full adder. We can see that the output S is an _____ between the input A and the half-adder SUM output with B and CIN inputs OR

XOR

NOR

NAND

8. Looking at the circuit diagram, COUT will only be true if any of the two inputs out of the three are LOW. FALSE

TRUE

9. Read the excerpt on full adders below and fill in the blanks
```It is possible to implement a full adder circuit
with the help of two half adder circuits.

A and B to produce a partial Sum.

The second half adder logic can be used to _
_____________________________________________

If any of the half adder logic
produces a carry, there will be an output carry.

Thus, COUT will be an OR function of the half-adder carry outputs.```

add the SUM to the final S output

produce the final SUM by adding 1 to whatever the output is

add the SUM to the first output produced and get the CIN output

add CIN to the Sum produced by the first half adder to get the final S output.

10. We want to be able to add two single bit numbers and also an incoming carry bit. In other words we effectively want to add ____________________
`Note: This is where full adders are very useful`

three single bit numbers

three double bit numbers

eight single bit numbers

four single bit binary 1s

11. For three binary bits there are ______ possible combinations

eight

four

16

two

12. Combining two half adders will produce a full adder without the need for any additional circuitry

TRUE

FALSE

13. The full adder is able to add three 1 bit numbers, the third bit is usually the ______________________

final sum

carry bit from the previous adder.

SUM of the half adder and OR gate

1 that is the output from the first half adder

14. Full adders can be ____________ to allow two numbers of any bit length to be added

combined with up to four AND gates

deleted

combined with a NAND gate

15. Coders can make sure their code is monitoring the __________ in case their calculations are out of range.

overflow flag

low outputs (0s)

output

high outputs (e.g 1s)