Answer: tracking and manipulating data.
Explanation: A spreadsheet is nothing more than a large ledger like the ones accountants and office workers used years ago. It was a ruled paper that data and information was entered on in order to keep track of money, inventory, and other information. Adding or subtracting from one column would change the totals and values overall. Now, with computers we have the electronic version and store the data on disc, flash drive or other connected media.
The obvious answer is
Layer 3, the network layer. but it's not always the case.
Point in case. Since firewalls essentially filter data, the answer depends on what kind of filtering you do.
If you filter based on IP address (for example), you can say that your firewall is filtering at layer 3. If you filter specific ports, you can say you're filtering at layer 4. If your firewall inspects specific protocol states or data, you can say it operates at layer 7.
The truth is that most firewalls do all these things in combination. So practically speaking there really is no useful answer to your question.
Explanation:
the right answer may be A.
10mb/s
------------------------------------