A) What is the initial configuration BPDU for B4? B) What is the configuration BPDU of B3 after receiving the initial configuration BPDU of B5? C) If B3 accepted B2 as the root, what is the configuration BPDU of B3? D) If B2 accepted B1 as the root through B7, what is the configuration BPDU of B2? E) Which bridge is the designated bridge of LAN C at this time? F) Now, if B5 accepted B1 as the root, what is the configuration BPDU of B3 after receiving the new configuration BPDU of B5? G) Which bridge is the designated bridge of LAN C at this time?