How many simultaneous calls could be placed on this link?

Refer to the exhibit.

Lighthorse Equine Management would like to investigate converging voice and data on their existing T1 Frame Relay WAN link between New York and Atlanta. Currently the following list of applications are consuming no more bandwidth than what is listed on this segment of the network.

T1 link 1536 kbps
e-mail 75 kbps
internet 200 kbps
Oracle 500 kbps
FTP 250 kbps
Total 1025 kbps

The customer has allocated 25% of the WAN link for routing updates and other overhead. They would like to increase the number of samples encapsulated in each PDU to 40 ms. You have calculated 6 bytes of overhead for Frame Relay, no cRTP, and the use of the G.711 codec. How many simultaneous calls could be placed on this link?

A.
0 calls

B.
1 call

C.
2 calls

D.
no more than 5 calls

E.
no more than 10 calls

F.
no more than 20 calls

Explanation:
Step 1, try to figure out the bandwidth for 1 call.
G711 codec: (0.04*64000bps)/8=320 bytes
IP/UDP/RTP: 40 bytes
Frame Relay: 6 bytes
1000/40=25 packets/second
Total BW for overhead: 320+40+6=366 bytes
Total BW in 1 second: 366*25=9150 bytes = 73.2kbps

Step 2, try to figure out how many BW in WAN can be used for calls.
1536kbps *(1-25%) 1025kbps = 127 kbps

So, just 1 call can be placed in this link.