Exercise 5, 6 and 9:

ex 5:

1. It's important to back up when you assemble a computer. That way, you won't make any mistakes.

2. Make sure you back up you data every day, in case you get a virus.

3. You need to install anti-virus software to protect the system. 

4. Invent a new password with 10 letters and numbers.

5. If the computer crashes when you're working on something, you may lose all your information. 

6. The file has probably been deleted, but let me see if l can recover.