CS-343 Assignment 1

Read Measurement And Units Of Measure (PDF) before answering the questions below.

1. Round 5,280 to the nearest power of ten.
2. Round 9 to the nearest power of ten.
3. 5,280 is ____ orders of magnitude larger than 9.
4. How many orders of magnitude larger than a picosecond is a microsecond?
5. Convert 25 nanoseconds to picoseconds.
6. Convert 25 nanoseconds to microseconds.
7. Convert 25 milliseconds to nanoseconds.
8. What is the “normal” representation of 52,800 µsec?
9. On the average, how many yes/no questions would you have to ask someone if they were thinking of a number between 1 and 32?
10. How many bits would you need to encode the digits 0 … 31?
11. Make up two different binary codes to represent the letters A, B, C, and D. Use the same, minimal, number of bits per letter in both codes.
12. Calculate the weighted average of the following values; show all work. Note that the sum of the Frequencies is 100, which can simplify the calculations.

    Value	Frequency
    70	10
    80	10
    90	80

13. At Queens College, grade point averages use the number of credits for each letter grade as the weights and the following table to relate letter grades to values:

    Grade	Value
    A+	4.0
    A	4.0
    A-	3.7
    B+	3.3
    B	3.0
    B-	2.7
    C+	2.3
    C	2.0
    C-	1.7
    D+	1.3
    D	1.0
    F	0.0

    What is the GPA of a student who has received A- in 2 courses, B+ in 3 courses, and B in 4 courses, if each course was 3 credits? Show all work.
14. What would be the GPA of the student in the previous question if they failed a 1-credit course in addition to receiving the grades listed in the question?
15. Show the terms needed to calculate how many bits would be needed to record 5 sec of CD-quality music (stereo). That is, do not do the calculation, but show what numbers would be multiplied together to get the answer.
16. List the values of the first eleven powers of two.
17. How many bits in 128 KB? Show all work.
18. A disk spins at 15,000 RPM. How long does it take to make one revolution? Answer in seconds, using the correct unit of measure to give a “normal” value with the integer part between 1 and 999.
19. How long would it take to transfer a 200 MB program from disk to main memory if the initial latency is 6 msec and the bandwidth of the channel between the disk and main memory is 500 Mbps? Show all work.
20. How long would it take to execute one million instructions if the average number of clock cycles per instruction is 2.5 and the clock speed is 2 GHz? Show all work.
21. “Computer A is twice as fast as computer B.” What does that mean in terms of how long it takes the two computers to execute a program?
22. Computer A takes 10 seconds to compute a program, and Computer B takes 5 seconds to compute the same program. Which computer is faster, and by how much? Answer by filling in the blanks in both of the following statements:
    • Computer ____ is ____ times faster than computer ____ .
    • Computer ____ is ____ % faster than computer ____ .

Type your name and your answers into the body of an email message (no attachments!), and send it to me: vickeryatbabbage.cs.qc.cuny.edu by midnight of the due date.

The Subject line of your email message must be: “CS-343 Assignment 1.”