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Q9. (i) Many new cars have systems to switch on windscreen wipers, cither automatically

When moisture is Detected. Or when they are Switched on manually by the driver. The system only operates if the ignition switch is on. A typical logic system for this operates as follows:

1.Ignition switch A outputs a logic I when it is switched on.

2.Moisture sensor B outputs a logic I when rain is detected.

3.Wiper switch C outputs a logic I when it is switched on by the driver.

4.The windscreen wiper motor operates when output X is at logic I.

Produce EACH of the following for this logic system with inputs A, B,C and output X:

(i) the truth table, including columns for A, B, C and X: (3)

(ii) a Boolean expression for output X in its simplest form: (5)

(iii) the logic circuit for the Boolean expression obtained in (ii) (2)

Determine EACH of the following, without using a calculator conversion function:

(i) the hexadecimal operation CF9F + EDAF:       (2)

(ii) the binary operation 10110     (2)

(iii) the conversion of DBCA to decimal.     (2)