Computer Science stuff

[johnny]

Okay, so these are the questions that came from my computer science textbook, and I answered them on my own, but the textbook does not give out the answers for these questions. I want to know if I answered these right. Any suggestions would be appreciated.

1. Suppose that only 50GB of your personal computer's 120GB hard-disk drive is empty. Would it be reasonable to use CDs to store all the material you have on the drive as a backup? What about DVDs?
I answered:
It would be reasonable to use CDs, because information is recorded in them by creating variations in their reflection surfaces. But, not really DVDs, because they usually work very well for multimedia and entire motion pictures.
2. How many bytes of storage space would be required to store a 400-page novel in which each page contains 3500 characters if ASCII were used? How many bytes would be required if Unicode were used?
I answered:
1 character in ASCII = 8 bits = 1 byte, 1 character in Unicode = 16 bits = 2 bytes
(400)(3500) = 1400000 characters
Thus, 1400000 bytes for ASCII, and 2800000 bytes for Unicode.
3. What values have binary representations in which only one of the bits is 1? List the binary representations for the smallest six values with this property.
I answered:
Possible binary representations: 0001, 0010, 0100, 1000, 10000, 100000
Therefore 1, 2, 4, 8, 16, and 32.

[WingedPanther]

For 1: think about the storage size of a CD/DVD and the amount of data that needs to be stored for a single backup. I would not consider CDs a viable format based on those calculations.

[John]

I too would not consider a CD a reasonable option. It would require 1000CD's. DVD's are a much better option IMO, Bluray would be even better.

[broncoslb]

Yea, that would still be about 11 DVDs. External hdd would be a much better solution.

As for #3, 10000000 would be -128 if you are working with signed values, so that could replace your 100000=32 on your list