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An introduction to binary codes and characters - Answers

Q1. There are 8 bits in a byte.
Q2. 7 bits are used in standard ASCII.
Q3. 27 = 128
Q4. The biggest whole number you can represent if you have 7 bits is 127. This is because we count from 0.
Q5. 8 bits are used in extended ASCII.
Q6. 28 = 256
Q7. The biggest whole number you can represent if you have 8 bits is 255. This is because we count from 0.
Q8. The character set nearly all personal computers use is ASCII.
Q9. D is 68, 97, 118, 105, 100 and is converted to 0100 0100,     0110 0001,     0111 0110,     0110 1001,     0110 0100
Q10. Preactical task: convert your own name.

Extension tasks
a) Zero is a known fixed amount whereas null there isn't a defined amount yet.
b) Practical task: see if you can memorise the general organisation of the ASCII table, including where null, 0, the spacea and A start.
c) The decimal codes from 0 - 31 in the ASCII table are not printable. They are control characters that you can send to peripherals e.g. a printer to control them. 

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