Homework 1 Data Representation Questions by iarthur


									Complete in your homework jotter and hand in on Thursday 3rd

1. ASCII and UNICODE are both used to represent text in computer

(a) Describe 1 advantage of UNICODE over ASCII                          1

(b) Describe 1 disadvantage of UNICODE over ASCII                       1

2. What is the 8 bit two’s complement representation of the number -72?

3. In floating point notation what defines:

(a) The range of the numbers stored?                                    1

(b) The precision or accuracy of the numbers stored?                    1

4. Describe how graphics are stored using a bit-mapped package          2

5. (a) What is the number 385 represented as a binary number?           1

(b) Represent the number -86 in 8 bit two’s complement                  1

(c) Write the number -37 as an 8-bit binary number using 2s complement
6. Ian purchases a new scanner. He scans photographs saving them as a
bit mapped image.

(a) Ian is aware that the quality of a bit mapped image depends on its bit
depth and resolution. What is meant by the terms:

(i) bit depth?                                                          1
(i) resolution?                                                        1

(b) Ian scans a photograph. The image is 800 by 600 pixels and uses
65,536 colours. Calculate the file size of the scanned image. Show all
working and express your answer in appropriate units                   4

7. John uses his digital camera to take photographs. It has a 512
Megabyte memory card. His camera uses 16,777,216 colours and is set to
a resolution of 3000 x 2000 pixels

(a) Calculate the file size of a single image. Your answer should be in
appropriate units. Show all working                                     3

(b) What is the maximum number of images of this size that can be stored
on John’s memory card?                                               2

To top