A group of 20 servers carry a traffic of 10 Erlangs. If average duration of calls is 3 minutes, calculate the no. of calls put through by a single server and a group as a whole in 1 hour period.

• A. 10 calls by single server and 200 calls by a group
• B. 8 calls by single server and 250 calls by a group
• C. 100 calls by single server and 200 calls by a group
• D. none of the above