$4.(8$ points$)$ Refer to the following network diagram. The letter id$$s refers to the layer $3$ address $($equivalent to an IP address$),$ the number id$$s refer to the layer $2$ addresses $($equivalent to an MAC address$).$ Host $1$ sends a frame to Host $2$ as illustrated with the red arrow.

a$)(6$ points$)$ Fill in the table below:

LAN $1$ LAN $2$ LAN $3$

Source Address Destination Address Source Address Destination Address Source Address Destination Address

Layer $3731682269919$

Layer $2$ A B A B A B

b$)(2$ points$)$ The number of direct and indirect frame$/$packet deliveries from Host $1$ to Host $2$ are $\_\_\_\_\_\_\_$ and $\_\_\_\_\_\_,$ respectively.