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(ii) TWO half-adders can be connected to form a full-adder as shown in Figure 4. This
circuit has THREE inputs.

Figure 4. DO NOT WRITE IN THIS AREA

Draw a table to show the outputs at points P, Q, R and S for the following input
states:

A. 11 = 1 I2 = 0 I3 = 1
B. 11 = 1 I2 = 1 I3 = 1 DO NOT WRITE IN THIS AREA

[2 marks] DO NOT WRITE IN THIS AREA
Total 30 marks

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