Which characteristic describes the default gateway of a host computer? O a. The logical address of the router interface on the same network as the host computer O b. The logical address of the router interface on a different network as the host computer O c. The physical address of the router interface on a different network than the host computer O d. The physical address of the router interface on the same network as the host computer What subnet mask is represented by the /18 notation? O a. 255.255.240.0 O b. 255.255.255.0 O c. 255.255.225.0 O d. 255.255.192.0